[Paid Software Announcement and Discussion] NamelessFragger:
Any attempts to run a backup with Flashfire immediately results in a force close.

Here's a logcat excerpt, if it helps.

I/ActivityManager( 1290): Start proc eu.chainfire.flash for activity eu.chainfire.flash/.ui.activity.MainActivity: pid=31296 uid=10092 gids={50092, 3003, 1028, 1015}
I/dalvikvm(31296): Could not find method android.view.ViewAnimationUtils.createCircularReveal, referenced from method eu.chainfire.flash.ui.activity.MainActivity.setProgressVisible
W/dalvikvm(31296): VFY: unable to resolve static method 16613: Landroid/view/ViewAnimationUtils;.createCircularReveal (Landroid/view/View;IIFF)Landroid/animation/Animator;
D/dalvikvm(31296): VFY: replacing opcode 0x71 at 0x006f
W/dalvikvm(31296): VFY: unable to find class referenced in signature (Landroid/view/SearchEvent;)
I/dalvikvm(31296): Could not find method android.view.Window$Callback.onSearchRequested, referenced from method android.support.v7.view.WindowCallbackWrapper.onSearchRequested
W/dalvikvm(31296): VFY: unable to resolve interface method 16805: Landroid/view/Window$Callback;.onSearchRequested (Landroid/view/SearchEvent;)Z
D/dalvikvm(31296): VFY: replacing opcode 0x72 at 0x0002
I/dalvikvm(31296): Could not find method android.view.Window$Callback.onWindowStartingActionMode, referenced from method android.support.v7.view.WindowCallbackWrapper.onWindowStartingActionMode
W/dalvikvm(31296): VFY: unable to resolve interface method 16809: Landroid/view/Window$Callback;.onWindowStartingActionMode (Landroid/view/ActionMode$Callback;I)Landroid/view/ActionMode;
D/dalvikvm(31296): VFY: replacing opcode 0x72 at 0x0002
I/dalvikvm(31296): Could not find method android.content.res.TypedArray.getChangingConfigurations, referenced from method android.support.v7.widget.TintTypedArray.getChangingConfigurations
W/dalvikvm(31296): VFY: unable to resolve virtual method 477: Landroid/content/res/TypedArray;.getChangingConfigurations ()I
D/dalvikvm(31296): VFY: replacing opcode 0x6e at 0x0002
D/dalvikvm(31296): GC_CONCURRENT freed 170K, 5% free 4328K/4524K, paused 3ms+2ms, total 21ms
I/dalvikvm(31296): Could not find method android.content.res.TypedArray.getType, referenced from method android.support.v7.widget.TintTypedArray.getType
W/dalvikvm(31296): VFY: unable to resolve virtual method 499: Landroid/content/res/TypedArray;.getType (I)I
D/dalvikvm(31296): VFY: replacing opcode 0x6e at 0x0002
I/dalvikvm(31296): Could not find method android.os.StatFs.getTotalBytes, referenced from method eu.chainfire.flash.ui.list.action.ActionBackupHandler.edit
W/dalvikvm(31296): VFY: unable to resolve virtual method 1257: Landroid/os/StatFs;.getTotalBytes ()J
D/dalvikvm(31296): VFY: replacing opcode 0x74 at 0x026f
D/dalvikvm(31296): GC_CONCURRENT freed 245K, 6% free 4561K/4832K, paused 1ms+6ms, total 16ms
E/ViewRootImple(31296): setView mWindowAttributes.type:1
D/libEGL (31296): loaded /system/lib/egl/libEGL_tegra.so
I/ (31296): Attempting to load EGL implementation /system/lib/egl/libEGL_tegra_impl
I/ (31296): Loaded EGL implementation /system/lib/egl/libEGL_tegra_impl
D/libEGL (31296): loaded /system/lib/egl/libGLESv1_CM_tegra.so
D/libEGL (31296): loaded /system/lib/egl/libGLESv2_tegra.so
E/Parcel (31296): Reading a NULL string not supported here.
E/Parcel (31296): Reading a NULL string not supported here.
E/Parcel (31296): Reading a NULL string not supported here.
E/Parcel (31296): Reading a NULL string not supported here.
E/Parcel (31296): Reading a NULL string not supported here.
D/AndroidRuntime(31335):
D/AndroidRuntime(31335): >>>>>> AndroidRuntime START com.android.internal.os.RuntimeInit <<<<<<
D/AndroidRuntime(31335): CheckJNI is OFF
D/dalvikvm(31335): Trying to load lib libjavacore.so 0x0
D/dalvikvm(31335): Added shared lib libjavacore.so 0x0
I/ (31296): Loading GLESv2 implementation /system/lib/egl/libGLESv2_tegra_impl
D/OpenGLRenderer(31296): Enabling debug mode 0
D/dalvikvm(31335): Trying to load lib libnativehelper.so 0x0
D/dalvikvm(31335): Added shared lib libnativehelper.so 0x0
W/ActionBarDrawerToggle(31296): DrawerToggle may not show up because NavigationIcon is not visible. You may need to call actionbar.setDisplayHomeAsUpEnabled(true);
D/AndroidRuntime(31338):
D/AndroidRuntime(31338): >>>>>> AndroidRuntime START com.android.internal.os.RuntimeInit <<<<<<
D/AndroidRuntime(31338): CheckJNI is OFF
D/dalvikvm(31338): Trying to load lib libjavacore.so 0x0
D/dalvikvm(31338): Added shared lib libjavacore.so 0x0
D/dalvikvm(31338): Trying to load lib libnativehelper.so 0x0
D/dalvikvm(31338): Added shared lib libnativehelper.so 0x0
I/ActivityManager( 1290): Displayed eu.chainfire.flash/.ui.activity.MainActivity: +359ms
I/dalvikvm(31335): Total arena pages for JIT: 11
D/AndroidRuntime(31335): Calling main entry com.android.commands.am.Am
D/dalvikvm(31335): Note: class Landroid/app/ActivityManagerNative; has 156 unimplemented (abstract) methods
D/AndroidRuntime(31335): Shutting down VM
E/ViewRootImple( 9052): setView mWindowAttributes.type:2005
D/dalvikvm(27412): GC_EXPLICIT freed 1K, 6% free 4287K/4528K, paused 2ms+2ms, total 23ms
I/dalvikvm(31338): Total arena pages for JIT: 11
D/AndroidRuntime(31338): Calling main entry eu.chainfire.flash.shell.Root
W/dalvikvm(31296): VFY: unable to find class referenced in signature (Ljava/nio/file/Path;)
W/dalvikvm(31296): VFY: unable to find class referenced in signature ([Ljava/nio/file/OpenOption;)
I/dalvikvm(31296): Could not find method java.nio.file.Files.newOutputStream, referenced from method okio.Okio.sink
W/dalvikvm(31296): VFY: unable to resolve static method 21639: Ljava/nio/file/Files;.newOutputStream (Ljava/nio/file/Path;[Ljava/nio/file/OpenOption;)Ljava/io/OutputStream;
D/dalvikvm(31296): VFY: replacing opcode 0x71 at 0x000a
W/dalvikvm(31296): VFY: unable to find class referenced in signature (Ljava/nio/file/Path;)
W/dalvikvm(31296): VFY: unable to find class referenced in signature ([Ljava/nio/file/OpenOption;)
I/dalvikvm(31296): Could not find method java.nio.file.Files.newInputStream, referenced from method okio.Okio.source
W/dalvikvm(31296): VFY: unable to resolve static method 21638: Ljava/nio/file/Files;.newInputStream (Ljava/nio/file/Path;[Ljava/nio/file/OpenOption;)Ljava/io/InputStream;
D/dalvikvm(31296): VFY: replacing opcode 0x71 at 0x000a
W/dalvikvm(31338): VFY: unable to find class referenced in signature (Ljava/nio/file/Path;)
W/dalvikvm(31338): VFY: unable to find class referenced in signature ([Ljava/nio/file/OpenOption;)
I/dalvikvm(31338): Could not find method java.nio.file.Files.newOutputStream, referenced from method okio.Okio.sink
W/dalvikvm(31338): VFY: unable to resolve static method 21639: Ljava/nio/file/Files;.newOutputStream (Ljava/nio/file/Path;[Ljava/nio/file/OpenOption;)Ljava/io/OutputStream;
D/dalvikvm(31338): VFY: replacing opcode 0x71 at 0x000a
W/dalvikvm(31338): VFY: unable to find class referenced in signature (Ljava/nio/file/Path;)
W/dalvikvm(31338): VFY: unable to find class referenced in signature ([Ljava/nio/file/OpenOption;)
I/dalvikvm(31338): Could not find method java.nio.file.Files.newInputStream, referenced from method okio.Okio.source
W/dalvikvm(31338): VFY: unable to resolve static method 21638: Ljava/nio/file/Files;.newInputStream (Ljava/nio/file/Path;[Ljava/nio/file/OpenOption;)Ljava/io/InputStream;
D/dalvikvm(31338): VFY: replacing opcode 0x71 at 0x000a
D/dalvikvm(31296): GC_CONCURRENT freed 205K, 5% free 4762K/5000K, paused 2ms+2ms, total 14ms
D/dalvikvm(31335): GC_CONCURRENT freed 100K, 18% free 504K/608K, paused 0ms+0ms, total 3ms
D/dalvikvm(31338): DexOpt: couldn't find static field Landroid/os/Build$VERSION;.PREVIEW_SDK_INT
W/dalvikvm(31338): VFY: unable to resolve static field 91 (PREVIEW_SDK_INT) in Landroid/os/Build$VERSION;
D/dalvikvm(31338): VFY: replacing opcode 0x60 at 0x0006
I/dalvikvm-heap(31338): Grow heap (frag case) to 13.293MB for 1048592-byte allocation
I/dalvikvm-heap(31338): Grow heap (frag case) to 19.405MB for 1048592-byte allocation
D/dalvikvm(31338): GC_CONCURRENT freed 11975K, 85% free 2200K/14176K, paused 1ms+0ms, total 11ms
W/ThrottleService( 1290): unable to find stats for iface rmnet0
I/dalvikvm(31296): Could not find method android.os.StatFs.getBlockSizeLong, referenced from method eu.chainfire.flash.shell.RootCommands$FreeSpace.asRoot
W/dalvikvm(31296): VFY: unable to resolve virtual method 1253: Landroid/os/StatFs;.getBlockSizeLong ()J
D/dalvikvm(31296): VFY: replacing opcode 0x6e at 0x000e
I/dalvikvm(31338): Could not find method android.os.StatFs.getBlockSizeLong, referenced from method eu.chainfire.flash.shell.RootCommands$FreeSpace.asRoot
W/dalvikvm(31338): VFY: unable to resolve virtual method 1253: Landroid/os/StatFs;.getBlockSizeLong ()J
D/dalvikvm(31338): VFY: replacing opcode 0x6e at 0x000e
D/AndroidRuntime(31338): Shutting down VM
D/dalvikvm(31338): GC_CONCURRENT freed 3880K, 92% free 1155K/14176K, paused 1ms+0ms, total 12ms
I/Finsky (26364): [880] com.google.android.finsky.billing.iab.o.a(157): eu.chainfire.flash: Account from first account - [QLaxnB_jjY6ENjD6rcLPteq9DDI]
I/Finsky (26364): [881] com.google.android.finsky.billing.iab.o.a(157): eu.chainfire.flash: Account from first account - [QLaxnB_jjY6ENjD6rcLPteq9DDI]
I/dalvikvm(31296): Could not find method android.graphics.drawable.Drawable.setHotspot, referenced from method eu.chainfire.flash.ui.list.action.ActionDisplay.animateBackgroundClick
W/dalvikvm(31296): VFY: unable to resolve virtual method 751: Landroid/graphics/drawable/Drawable;.setHotspot (FF)V
D/dalvikvm(31296): VFY: replacing opcode 0x6e at 0x002a
D/dalvikvm(31296): GC_CONCURRENT freed 226K, 5% free 4930K/5184K, paused 3ms+1ms, total 18ms
I/ActivityManager( 1290): START u0 {cmp=eu.chainfire.flash/.ui.activity.OptionsActivity (has extras)} from pid 31296
E/ViewRootImple(31296): setView mWindowAttributes.type:1
I/dalvikvm(31296): Could not find method android.content.res.Resources.getDrawable, referenced from method android.support.v7.widget.ResourcesWrapper.getDrawable
W/dalvikvm(31296): VFY: unable to resolve virtual method 440: Landroid/content/res/Resources;.getDrawable (ILandroid/content/res/Resources$Theme;)Landroid/graphics/drawable/Drawable;
D/dalvikvm(31296): VFY: replacing opcode 0x6e at 0x0002
I/dalvikvm(31296): Could not find method android.content.res.Resources.getDrawableForDensity, referenced from method android.support.v7.widget.ResourcesWrapper.getDrawableForDensity
W/dalvikvm(31296): VFY: unable to resolve virtual method 442: Landroid/content/res/Resources;.getDrawableForDensity (IILandroid/content/res/Resources$Theme;)Landroid/graphics/drawable/Drawable;
D/dalvikvm(31296): VFY: replacing opcode 0x6e at 0x0002
I/dalvikvm(31296): Total arena pages for JIT: 11
I/ActivityManager( 1290): Displayed eu.chainfire.flash/.ui.activity.OptionsActivity: +180ms
D/dalvikvm(31296): GC_CONCURRENT freed 98K, 3% free 5223K/5348K, paused 2ms+4ms, total 21ms
I/HK/LatinKeyboardBaseView( 1800): closing org.pocketworkstation.pckeyboard.LatinKeyboardView{421da4b8 V.ED.... ......ID 0,0-1920,485 #7f07000a app:id/LatinkeyboardBaseView}
D/dalvikvm( 1290): GC_FOR_ALLOC freed 1750K, 40% free 13754K/22708K, paused 49ms, total 50ms
D/AndroidRuntime(31296): Shutting down VM
W/dalvikvm(31296): threadid=1: thread exiting with uncaught exception (group=0x41cac930)
E/AndroidRuntime(31296): FATAL EXCEPTION: main
E/AndroidRuntime(31296): java.lang.NoSuchMethodError: android.os.StatFs.getTotalBytes
E/AndroidRuntime(31296): at eu.chainfire.flash.ui.list.action.ActionBackupHandler.edit(ActionBackupHandler.java:294)
E/AndroidRuntime(31296): at eu.chainfire.flash.ui.list.action.ActionBackupHandler.add(ActionBackupHandler.java:209)
E/AndroidRuntime(31296): at eu.chainfire.flash.ui.list.action.ActionBackupHandler.onActivityResult(ActionBackupHandler.java:86)
E/AndroidRuntime(31296): at eu.chainfire.flash.ui.list.action.ActionDisplayManager.onActivityResult(ActionDisplayManager.java:305)
E/AndroidRuntime(31296): at eu.chainfire.flash.ui.fragment.ActionDisplayFragment.onActivityResult(ActionDisplayFragment.java:166)
E/AndroidRuntime(31296): at android.support.v4.app.FragmentActivity.onActivityResult(FragmentActivity.java:156)
E/AndroidRuntime(31296): at eu.chainfire.flash.ui.activity.MainActivity.onActivityResult(MainActivity.java:569)
E/AndroidRuntime(31296): at android.app.Activity.dispatchActivityResult(Activity.java:5293)
E/AndroidRuntime(31296): at android.app.ActivityThread.deliverResults(ActivityThread.java:3315)
E/AndroidRuntime(31296): at android.app.ActivityThread.handleSendResult(ActivityThread.java:3362)
E/AndroidRuntime(31296): at android.app.ActivityThread.access$1100(ActivityThread.java:141)
E/AndroidRuntime(31296): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1282)
E/AndroidRuntime(31296): at android.os.Handler.dispatchMessage(Handler.java:99)
E/AndroidRuntime(31296): at android.os.Looper.loop(Looper.java:137)
E/AndroidRuntime(31296): at android.app.ActivityThread.main(ActivityThread.java:5039)
E/AndroidRuntime(31296): at java.lang.reflect.Method.invokeNative(Native Method)
E/AndroidRuntime(31296): at java.lang.reflect.Method.invoke(Method.java:511)
E/AndroidRuntime(31296): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
E/AndroidRuntime(31296): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
E/AndroidRuntime(31296): at dalvik.system.NativeStart.main(Native Method)
W/ActivityManager( 1290): Force finishing activity eu.chainfire.flash/.ui.activity.MainActivity
E/ViewRootImple( 1290): setView mWindowAttributes.type:2003
W/ActivityManager( 1290): Activity pause timeout for ActivityRecord{428d6a30 u0 eu.chainfire.flash/.ui.activity.MainActivity}
I/Finsky (26364): [1] com.google.android.finsky.utils.df.onTrimMemory(25): Memory trim requested to level 20
I/Process (31296): Sending signal. PID: 31296 SIG: 9
I/ActivityManager( 1290): Process eu.chainfire.flash (pid 31296) has died.

This is on a Wacom Cintiq Companion Hybrid, 4.2.1 Jelly Bean (never had any official updates), rooted with SuperSU.

I was hoping to make a full backup before I attempt to test any future custom recoveries or ROMs, but even the ID backup fails with an instant force close. Something else is at play here.