OK, you are right man. I built a simple app, adding to it with each version. Tested using Test Anywhere on my Phone with applab
1. Simple App with:
Sprite1: Acts as a button
Sprite2: Character, Behaviours- moveto, stay in layout
Pressing the button causes sprite2 to move to random positions.
Test - Passed
2. Added a Background image, 640,960
Test - Passed
3. Added spritefont object, image is 4608x128
Test Failed
Maybe it's large images, or maybe it's spritefont. I'll do more testing to see.