Greetings to everybody!

Trying to play BITAW on my WinXP-32/GeForce GT730. Both GOG 2.06 version and ISO patched to 2.08 have the same glitch. Menu starts fine but when trying Tutorial or Campaign I get something like this (see attachment). The source of these rotating glitch-rays is in the upper left corner of the screen. When starting, a Setup menu appears (only once, at the first run), changing options there does nothing. DxWnd doesn't help.

What is the nature of this glitch? Z-buffer? EMBM? Something else? And what could be a remedy?