My guess is that you designed your layout using HD resolution, and the Premiere+ is not scaling correctly.
Premiere+ has an FHD UI (1920x1080), where I believe the 3 has an HD UI display (1280x720).
This means the menus and screens and stuff (not the video itself) are using different resolutions.
Try adding this to your manifest:
ui_resolutions=hd
This will tell the firmware that you designed your UI for HD, and will automatically upscale when necessary.