Help tweaking multiAVCHD menu

[glitt]

I've loaded in all my media files and in my menu preview I'm able to navigate left and right to flick between them, but once burned onto a bluray, the navigation doesn't work. The video thumbnail just appears black and when I try to use any navigation buttons the screen will go black and then the menu will reset (When testing on my ps5, pressing any button refreshes the menu screen and 'x' will just play the first video in the list. I also cant get it working with Leawo)

I have only the main menu activated. Chapter menu, setup menu and title list menu are turned off. Also the navigation screen really confuses me so I wonder if I've done something wrong there?

Hoping someone can notice my glaringly obvious mistakes!