(snip
: So I reinstalled everything and ANY terminal I go to
: to the left of the text it says picture not found....
: Anyone know how to help?
This can happen for at least two reasons:
1) When playing cooperative and a joining player doesn't have a local copy of the map (or the game *thinks* he doesn't). Marathon doesn't transmit the term pictures when sending the map.
2) Map is lacking said terminal pictures; or, the terminal has an error and refers to the wrong PICT.
For your case, it seems most likely that when converting the map the second time you made a mistake and didn't transfer the PICT resources properly.
BTW, are you running Aleph One? Full-screen causes problems for me too, but never crashes.