@zerojay The extensions were missing from es_systems.cfg in the openbor section; I just had to add them😊. It's launching now!!! Thank you so much for all your help guys. Really appreciate it.

You are truely a hero!
Your solution works very well. I have tested the easyrpg player with my homemade RPG and it works, as far as I have played, without any differences compered to the windows pc version.

Thanks a lot!

@BuZz https://retropie.org.uk/forum/topic/27043/libpng-dev-not-installed-x86

@macsgv Thanks, but any chance you could do a quick writeup?
I hate "watching" tutorials on principle - plus it's in Spanish and does not seem to refer to lr-hatari anyway.