"Theming" Problem - Android Q&A, Help & Troubleshooting

Hey guys, I don't know if this is 100% the right section to post this.
I just started to "theme" WhatsApp.
It's another version of "Yorzua" i used to "port" this theme.
It's just for personal usage. I decompiled his Themed version. (I used his one, to put his theme to the updated WhatsApp-Version.
I made it to "solve" some issues that appeard while recompiling.
I put the images to the new version of WhatsApp. Most of the theme is working.
The App is running fine. I changed the Appname for my girlfriend^^
Now to my problem.
I can use everything. But when i receive a picture (havn't tried it with other media yet) and i try to open it afterwards it loads, loads, loads and fc's.
Now here is my problem. In school I had C#. But that's 2 years ago^^ And since then i havn't done anything except a little programm.
I don't know how to find the issue now. Is there any way to debug this on my phone and see which file got a problem?

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Okay, i just made a logcat while doing the same step.
I hope someone got a clue and might help me. Thanks in advance
PS: I removed the unimportant parts
Code:
09-22 16:22:22.959 21964 21964 I dalvikvm: Could not find method com.whatsapp.MediaView.a, referenced from method com.whatsapp.df.a
09-22 16:22:22.959 21964 21964 W dalvikvm: VFY: unable to resolve static method 3123: Lcom/whatsapp/MediaView;.a (Lcom/whatsapp/yz;Ljava/lang/String;Landroid/content/Context;)Landroid/content/Intent;
09-22 16:22:22.959 21964 21964 D dalvikvm: VFY: replacing opcode 0x71 at 0x006c
09-22 16:22:23.989 21964 21964 D AndroidRuntime: Shutting down VM
09-22 16:22:23.989 21964 21964 W dalvikvm: threadid=1: thread exiting with uncaught exception (group=0x40f95300)
09-22 16:22:23.994 21964 21964 E AndroidRuntime: FATAL EXCEPTION: main
09-22 16:22:23.994 21964 21964 E AndroidRuntime: java.lang.NoSuchMethodError: com.whatsapp.MediaView.a
09-22 16:22:23.994 21964 21964 E AndroidRuntime: at com.whatsapp.df.a(df.java:65)
09-22 16:22:23.994 21964 21964 E AndroidRuntime: at com.whatsapp.zn.onClick(zn.java:2)
09-22 16:22:23.994 21964 21964 E AndroidRuntime: at android.view.View.performClick(View.java:4211)
09-22 16:22:23.994 21964 21964 E AndroidRuntime: at android.view.View$PerformClick.run(View.java:17267)
09-22 16:22:23.994 21964 21964 E AndroidRuntime: at android.os.Handler.handleCallback(Handler.java:615)
09-22 16:22:23.994 21964 21964 E AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:92)
09-22 16:22:23.994 21964 21964 E AndroidRuntime: at android.os.Looper.loop(Looper.java:137)
09-22 16:22:23.994 21964 21964 E AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:4898)
09-22 16:22:23.994 21964 21964 E AndroidRuntime: at java.lang.reflect.Method.invokeNative(Native Method)
09-22 16:22:23.994 21964 21964 E AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:511)
09-22 16:22:23.994 21964 21964 E AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1006)
09-22 16:22:23.994 21964 21964 E AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:773)
09-22 16:22:23.994 21964 21964 E AndroidRuntime: at dalvik.system.NativeStart.main(Native Method)
09-22 16:22:24.034 2544 2664 E android.os.Debug: [email protected] > dumpstate -k -t -z -d -o /data/log/dumpstate_app_error