Problem running Custom Robo and Custom Robo v2

[jinryuuzen]

Both of these games use sprites to represent characters on top of polygon backgrounds. For some reason the emulators I have tried (1964, PJ64, nemu) refuse to let sprites move up and down slopes, rendering the games nigh unplayable. During the games' battles the textures for the backround and terrain flash off (mostly) and on(for fleeting moments) and are solid black when off, making it impossible to tell where one is on the battlefield.

Here's my system specs:
2.6 ghz P4
512 megs of DDR ram (I forget what speed)
Intel Extreme Graphics 2 64 meg integrated video (piece of junk...)
Running WinXP SP1 and Directx 9.0c

 

[jinryuuzen]

Some clarification:
Out of battle sprites refuse to negotiate changes in slope.
In battle background textures don't display most of the time