One game I cannot get to work even with flycast is Hydro Thunder. I get a black screen after the Dreamcast logo.

@mitu

Sure i " said in Reicast doesn't work properly" because i solved after this topic and hope to solve completely all even with this problem in controller.

So the adapter emulates 2 joysticks, but only one is actually connected/working ?

Yes, it's all right.

@toto2000 I would copy past the info you provided into a new thread. Its not going to get as much visibility here.

Nobody has any ideas?

Go here and scroll down to the bottom.

https://retropie.org.uk/docs/Dreamcast/

@ecks Did you test those files with some other emulators (eg: nullDC for pc) just to check their validity ?