Probably a problem with the sea directory, ship type, group definitions in the convoy layer, or a all of the above.
More then likely when i was going through the convoy layers, i missed a ship type that is being called upon that doesn't exist in the sea directory, OR ship type incompatiblity. Meaning, ship type X is being called in the campaign files when in the sea and roster directory its being declared as ship type Y.
It's not an easy thing trying to do a supermod/megamod, mostly by yourself. Mistakes will be made. In hindsight i shouldn't have attempted this project after working on TMO. Burnout level was high. I think in the future, i will not be going "lonewolf" if i continue.
EDIT: I wonder though, did you have any mod installed beforehand? Maybe some residual directories or files got left in the SH4 data directory. I wonder this because if any convoy contact caused a CTD, then:
a.) People would have screamed at me very loudly by now
OR
b.) Nobody's bothered to even attempt genuine playthrough, so it hasn't been reported until now. After all this time, if this is the first genuine attempt to at a play on this mod (albeit a beta), i see no reason to continue it ever again. Seriously, it took this long before someone said something?