It seems that after playing Morrowind for a while, GCD starts to throw errors when loading a game, or starting a new game for me. The error is

Expression Error Unable to find object "^G@@@@@@@@@@@@@@@@@@@@" in script Gals__Upgrade_Initialise.

I'm using a copy of GCD v 1.08, from the file
GCD v1.08 with Startscript, fixed [Galsiah].rar

I don't happen to remember where I downloaded it from.

EDIT: I suppose I should mention, it's fairly random when it will do this, and if the game loads, then there's no problems with it for that session of playing Morrowind.

Yes, this is a known problem. It happened to me but I was able to continue. IIRC, I had to try twice. Several modders have tried to fix it, you're using the latest attempt, but I don't have any hope for a true fix at this point. In most cases you can continue with reloading; I hope that works in your case.

It does work, but it often takes several tries (Upwards of 15-20 in some cases before the game will load cleanly)

There are two different types for 1.08 (one is 1.08kai2) and there's also v2.03 lean, so maybe you can try one of those instead.