I'm on version 20 or something of my map and all of a sudden I've started getting annoying problems.

Recently I had the The command failed. Windows reported the error:
"The system cannot find the file specified." error which I managed to fix.

Now whenever I run the map and walk through it the game runs extremely slow and choppy and then eventually crashes to desktop and presents the message box: "Engine Error. Internal driver error in IDirect3DDevice9::Present()".

This doesn't happen on any other maps just the newly compiled ones. I tried deleting some changes I had made since the last successful compile but that didn't help.

Any suggestions? I can't find anything useful on google.

Well judging from the name its a "direct3d" error which is basically 3d rendering, is your dod running in opengl? seems like its running in D3D

DoD Source only uses direct-x.

IDirect3DDevice9 <- would suggest his dod is running in direct3d or software mode and not openGL. It's my theory anyways.

if you test your map with all setting set at high, I did that and at some point, when the map is bigger, I needed to lower my setting to not crash on the desktop. I beleive it's a question of you have not enough ressources. I would lower all setting to minimum and try it again. I am pretty sure it will not crash.

Yeah ok I'll try that but I still need to stop if from doing the same thing on other peoples computers when I release it.

Nope, that made no difference.

I'm sure this thread is dead but just incase anyone else is experience similiar problems, I sorted them all out by .... duh duh duuuuh... putting hint brushes in my map :| Now runs smooth as a babies rear end.