[Xposed Framework Modules] dundua:
From my limited testing of saving stories, I have found the following bugs.

Saved videos do not save along with their image overlays, such as drawings or geofilters

Some videos save with a unix timestamp of 0, resulting in some videos not saving due to the same file name

Changed settings in Snapprefs do not take effect until I force close and reopen snapchat and snapprefs

Tested with Android 4.4 x86 in Virtualbox on a Windows 7 x64 host.

----------------- SNAPPREFS HOOKED -----------------
SnapChat Version: 9.13.0.0 (705)
SnapPrefs Version: 1.4.3 beta 3 (12)

~~~~~~~~~~~~ SNAPPREFS SETTINGS
FullCaption: false
SelectAll: false
SelectStory: false
HideBF: false
HideRecent: false
ShouldAddGhost: false
TxtColours: false
BgColours: false
Size: false
Transparency: false
Rainbow: false
Background Transparency: false
TextStyle: false
TextGravity: false
CustomFilters: false
CustomFiltersLocation: /storage/emulated/0/Snapprefs/Filters
mSpeed: false
mSpeedValue: 0.0
mLocation: false
mLatitude: null
mLongitude: null
mDiscover: true
mColours: false
*****Debugging: true *****
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
----------------------- SAVING SETTINGS -----------------------
Preferences have changed:
~ mModeSnapImage: SAVE_AUTO
~ mModeSnapVideo: SAVE_AUTO
~ mModeStoryImage: SAVE_AUTO
~ mModeStoryVideo: SAVE_AUTO
~ mTimerMinimum: 0
~ mToastEnabled: true
~ mToastLength: 0
~ mSavePath: /storage/sdcard1/Snapprefs
~ mSaveSentSnaps: true
~ mSortByCategory: true
~ mSortByUsername: true
~ mTimerUnlimited: false
~ mHideTimer: true
SnapPrefs: We are in DataSaving.initMethod
SnapPrefs: We are in DataSaving, we have class 1
SnapPrefs: We are in DataSaving, we have class 2
SnapPrefs: We are in DataSaving, we have class 3
SnapPrefs: We are in DataSaving, denied Discovery
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw2159909240220507269.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video already exists
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw21-107913075208289996.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video already exists
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw21-1895757192093206652.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video already exists
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw218842927215038622359.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video already exists
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw214634847473667046941.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video already exists
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw217483873302907259167.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_09-12-52-054.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30386
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw211272964087775352855.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_09-12-52-060.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30387
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw21-2079128969396722191.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_10-30-26-241.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30388
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw21-3110135438032859116.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_1969-12-31_16-00-00-000.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30381
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw21-3212535503359114012.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
java.lang.NullPointerException
at de.robv.android.xposed.XposedHelpers.getObjectField(XposedHelpers.java:611)
at com.marz.snapprefs.Saving.saveReceivedSnap(Saving.java:357)
at com.marz.snapprefs.Saving.access$000(Saving.java:44)
at com.marz.snapprefs.Saving$1.afterHookedMethod(Saving.java:103)
at de.robv.android.xposed.XposedBridge.handleHookedMethod(XposedBridge.java:645)
at android.widget.VideoView.setVideoURI(Native Method)
at android.widget.VideoView.setVideoURI(VideoView.java:233)
at android.widget.VideoView.setVideoPath(VideoView.java:229)
at apk.a(SourceFile:40)
at apk$1.a(SourceFile:152)
at apl$1.onPostExecute(SourceFile:48)
at android.os.AsyncTask.finish(AsyncTask.java:632)
at android.os.AsyncTask.access$600(AsyncTask.java:177)
at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:645)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5001)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)
at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:132)
at dalvik.system.NativeStart.main(Native Method)
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw218445607080310642542.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_11-29-43-431.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30389
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw21-3076091442966377744.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_11-29-56-604.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30390
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw218515274673341648792.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_11-39-45-652.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30391
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw21401381063700598083.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_13-29-00-719.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30392
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw212357407395425602730.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_13-30-13-295.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30393
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw216155593421795971064.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video already exists
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw216088361047930921875.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video already exists
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw21-4882058942471953102.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_15-50-50-315.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30394
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw21-8696866445439853531.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_15-51-50-935.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30395
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw21-7285059866276236386.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: IMAGE OR URI IS NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_16-01-28-699.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30396
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: It is a Bitmap
----------------------- SNAPPREFS ------------------------
SnapPrefs: THEY ARENT NULL
SnapPrefs: Image story opened
SnapPrefs: Mode: auto save
SnapPrefs: SAVEIMAGE DONE
SnapPrefs: Image story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_16-02-59-038.jpg
SnapPrefs: MediaScanner started
SnapPrefs: Saving image
SnapPrefs: MediaScanner scanned file: content://media/external/images/media/30397
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw21-8071233196807449264.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: THEY ARENT NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_16-15-29-397.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30398
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw21-6343670551885459292.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: THEY ARENT NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video already exists
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw21-6560068259475378271.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: THEY ARENT NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video already exists
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw214358948473188088720.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: THEY ARENT NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_18-09-52-369.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30399
SnapPrefs: Starting to view a snap, plus viewingSnap: true
SnapPrefs: Starting to view a snap
SnapPrefs: /data/data/com.snapchat.android/cache/uv/sesrh_dlw2118458441043551515.mp4.nomedia
SnapPrefs: It is a Video
----------------------- SNAPPREFS ------------------------
SnapPrefs: THEY ARENT NULL
SnapPrefs: Video story opened
SnapPrefs: Mode: auto save
SnapPrefs: Video story has been saved
SnapPrefs: Path: /storage/sdcard1/Snapprefs/Stories/nyclife1/nyclife1_2015-07-30_18-10-19-921.mp4
SnapPrefs: MediaScanner started
SnapPrefs: MediaScanner scanned file: content://media/external/video/media/30400