as Anton Zed said:
"Also it looks like some files are missing."
This could be a big problem, not to mention that your video card and sound card may be taking up a lot/some of that 512 MB of system memory you had/have

.
What I would do, at the bare minimum, is to see if I couldn't get Stardock Central d/l'ed (downloaded - sorry if you already know that abbr.) and try to see if can't repair those missing files...or, at the very least, if you have the CD's, reinstall the game - yeah, it sucks, but it may save some hard-earned time

.
Also, although I haven't run through the debug as you seemed to have, it seems that all the bad stuff (files missing/corrupted possibly) are happening during the beginning stages of the game or at startup, so it could be either something you could look into or just re-installing or, at the most extreme case, filing a bug report/request for tech help, yes?
Because it just looks like the beginning foul-ups are ruining the latter games stages for you, yes?
So, in summary, try these steps (from a computer enthusiast, not a technician

) :
1. check the memory specs on your PCI cards (video/audio) and see how much of that 512 MB they're using up.
1b. if they're using a pretty penny, memory wise, you may want to do what gallagher suggested and try and ask for more system RAM for you for whatever holiday(s) you celebrate

.
2. try and either d/l stardock central and see if the pre-release patches can't help but fix the incongruencies (sp? Go Me! lol - j/k) in your game directories

.
2b. and/or just try and re-install the game if you can. If you direct2drive'd it, it may take longer than usual...I don't know. sorry.
3. cheer up. I think you have the minimum specs to play it if you just tweak some things that others before me have said and just do some general virtual maintenance on your comp (i.e. getting rid of some system tray things, yes? I know I'm sometimes a sucker for those...they're So conveinient

)
4. rinse and repeat Endlessly (- Pinky and the Brain quote

)