Texture loading now works, provided the source image already has an alpha channel. The main menu shows and is usable (I'm mapping the dpad of the wiimote to the cursor keys).
New problems:
The Unix timer functions don't work.
The map parser corrupts the stack. I'm using the good old hardcoded map for now.
Several things just hang the console without a crash hexdump. One of them is playing
Well, looks like I'll have to look at the debugging possibilities.