the crowd in the mall in level 3 doesn't always seem to spawn for everyone. that's another known bug (last screenshot) but you can kill them if they do it's fun :P
run it in windows 7 sp2 compatibility mode. it's an FPSC X9 game and idk if that was really planned to work on win10. none of my FPSC games even work in 8. I use 7.
yeah the maps pretty basic and boxy from the outside. FPSC is an engine known for its collision problems. be careful in combat and just try not to die even once and it might not glitch out