Just to recap, the three most important (and very small) changes I did on top of the included maemo patch were:

Add -lX11 to link flags. This was enough to build the whole package and get it running as well.

Added RX-51 to the list of keyboard-equipped Maemo devices

Commented out the SDL_WM_SetIcon call. This enabled getting window focus -> enabled you to use the keyboard.


The rest is just trying to get the keyboard mappings to such a state that they make sense on the N900 - and I'm still missing the ability to enter the save dialog and enter numbers - the keyboard command part of the code is a bit confusing there and I don't know SDL anyway.
Also I enabled the SCI and SCI32 engines because I wanted to play Quest for Glory 2.