I noticed that this most recent error message appeared after loading a game, but the one you posted before occured after using a transfer player command, both of which go through RMX-OS. Perhaps Blizz, you can look for what is happening before Game_System is loaded in both of these RMX-OS methods. Because I'm pretty sure everything makes sense from the Blizz-ABS side.
Also, I just wanted to check if it was a save data problem. Does the error occur when you start a new game whitespirits? If everything works on a new game, I can send you a script that will patch your savegames so you don't have to lose any progress.