[Xperia Z2 Q&A, Help & Troubleshooting] Helbelinc:
I don't know if this is what you need or if I did it correctly, but here's a debug log I've made via SDK (see attachment; I've roughly inserted the time from starting the app to crashing. I just don't really know how to read code/logs ...)

As far as I can say, this is the relevant part:

03-29 22:01:04.659 18133 18133 E AndroidRuntime: FATAL EXCEPTION: main

03-29 22:01:04.659 18133 18133 E AndroidRuntime: Process: com.samsung.android.app.watchmanager, PID: 18133

03-29 22:01:04.659 18133 18133 E AndroidRuntime: java.lang.NoClassDefFoundError: Failed resolution of: Lcom/samsung/android/feature/FloatingFeature;

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at com.samsung.android.app.watchmanager.sdllibrary.FloatingFeature.getEnableStatus(FloatingFeature.java:11)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at com.samsung.android.app.twatchmanager.log.LoggerUtil$Builder.<clinit>(LoggerUtil.java:95)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at com.samsung.android.app.twatchmanager.util.HostManagerUtils.startPluginActivity(HostManagerUtils.java:551)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at com.samsung.android.app.watchmanager.setupwizard.HMConnectFragment.callPluginActivity(HMConnectFragment.java:377)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at com.samsung.android.app.watchmanager.setupwizard.HMConnectFragment.callPluginActivityWithDelay(HMConnectFragment.java:365)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at com.samsung.android.app.watchmanager.setupwizard.HMConnectFragment.access$200(HMConnectFragment.java:67)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at com.samsung.android.app.watchmanager.setupwizard.HMConnectFragment$1.handleMessage(HMConnectFragment.java:315)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at android.os.Handler.dispatchMessage(Handler.java:102)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at android.os.Looper.loop(Looper.java:234)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at android.app.ActivityThread.main(ActivityThread.java:5526)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at java.lang.reflect.Method.invoke(Native Method)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)

03-29 22:01:04.659 18133 18133 E AndroidRuntime: Caused by: java.lang.ClassNotFoundException: Didn't find class "com.samsung.android.feature.FloatingFeature" on path: DexPathList[[zip file "/data/app/com.samsung.android.app.watchmanager-1/base.apk"],nativeLibraryDirectories=[/data/app/com.samsung.android.app.watchmanager-1/lib/arm, /data/app/com.samsung.android.app.watchmanager-1/base.apk!/lib/armeabi-v7a, /vendor/lib, /system/lib]]

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at dalvik.system.BaseDexClassLoader.findClass(BaseDexClassLoader.java:56)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at java.lang.ClassLoader.loadClass(ClassLoader.java:511)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at java.lang.ClassLoader.loadClass(ClassLoader.java:469)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	... 13 more

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	Suppressed: java.lang.ClassNotFoundException: com.samsung.android.feature.FloatingFeature

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at java.lang.Class.classForName(Native Method)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at java.lang.BootClassLoader.findClass(ClassLoader.java:781)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at java.lang.BootClassLoader.loadClass(ClassLoader.java:841)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	at java.lang.ClassLoader.loadClass(ClassLoader.java:504)

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	... 14 more

03-29 22:01:04.659 18133 18133 E AndroidRuntime:	Caused by: java.lang.NoClassDefFoundError: Class not found using the boot class loader; no stack trace available

03-29 22:01:04.661 4105 7141 D ActivityManager: New dropbox entry: com.samsung.android.app.watchmanager, data_app_crash, d2aadc2f-d5ff-4528-a9bd-95d85b1002d3

03-29 22:01:04.671 4105 7141 W ActivityManager: Force finishing activity com.samsung.android.app.watchmanager/.setupwizard.SetupWizardWelcomeActivity

03-29 22:01:04.718 4105 8050 E InputMethodManagerService: Ignoring shouldOfferSwitchingToNextInputMethod due to an invalid token. uid:10197 token:null