Nice digging, drone. So far, I can confirm that the MTW First Crusade 1099 file you linked to is not the mod created by Grell, but a different crusade mod altogether. It would seem that I was the last person lucky enough to get a copy of Grell's mod before it got taken off of AtomicGamer (unless someone can prove me wrong).

Also, very nice find with the Interregnum mod! I downloaded it and gave it a try. (Installation requires that you replace several folders in the main directory, as well as the main directory itself, but no biggie.) The mod seems to work fine, though I haven't had a chance to play more than three turns of a given campaign. I plan to give it a whirl as the English. (The unit rosters are the same or similar to the ones that Grell used in The First Crusade mod; unfortunately, Grell didn't get around to figuring out how to add more than 20 factions without random CTDs.) Anyway, I hope others can (re)discover this fine mod, as well.

@ BKB: Nice to see you still haunt these forums from time to time. Your great work resonates with a lot of us, even after all these years! In fact, I was about getting my a$$ kicked in the Supermod––playing as the Teutonic Knights––just the other day! Age of Warlords is also a gem. Thank you, good sir.