hi there.
If you try to run the mod without a CoH disc, CoH eventually prompts you to insert an opposing fronts disc.
It will NOT accept a Tales of Valor disc, for example, as a substitute.
However, as long as you start the mod WITH your tales of valor disc inserted... it's fine.
It also appears that once the disc has been validated by the Eastern Front mod, you no longer need the disc (i.e. I can now run EF mod without any prompts for discs... although I've not tested this after a reboot).
I hope this helps anyone who's stuck with this.
Thanks,
Gary