Hello. Apologies for the delay in replying.
I think you have identified a bug in Bridge Command (it's actually an underlying problem with Blitz3D), where very large image files do not load correctly.
To work around this problem, please re-save the radar image and texture (radar.bmp and bcterrain.bmp) as JPEG images, and update the terrain.ini file. When I tested this, your world model then seemed to load correctly. Please let me know if you have any problems.