Part 2/2:

Dirt Trax FX, fixes the fact that it was only displaying half the polygons:

Voxel Demo, fixes rendering:

Vortex, fixes Z-buffering:

Edit: I'm going to go out on a limb here and say that the remaining issues in Yoshi's Island are NOT SuperFX-related. This is just based on the fact that things like the pause screen work perfectly, and the garbled graphics that are being displayed are being displayed in tiles, and using tile sets the SuperFX would not have available to it. In that case, over to you, Kale. smile