This is an older, buggy 2.5-D implementation. I refer you to my new, 3-D tech demo, "Blue Sky:"
Notes on CAPX file:
If you make "view angle" 0, you have Platform, and 90 is 8-direction. Everything in between is 2.5-D! With the newest version, you can place your floor pieces as if it were a top-down game, manually input the Z-coordinate, and their positions and heights will adjust automatically to fit the perspective. When placing walls (brown), put them at the (x,y) coordinates you want and specify the top and bottom z values; positioning and height will calculate automatically!