Thanks to OP and Southern for posting links to the few (only?) community-made campaigns.
I tried the campaign from the first link, Sarrodinodin the Storm Priest , both are done by the same creator.
If you are a 4X gamer that likes to take your time and play with your own play style, DO NOT play these campaigns. The author is somewhat of a control freak and forces you to play in certain way. Can't take your time (turn limits on most maps), and random raiding parties that teleport to you out of nowhere on scripted queues wipe you out and throw off any sort of balance, while you face traditional adversaries head-on.
As a last resort to try to muster any enjoyment out of his content, I even downloaded the AoW1 developer campaign editor to try and remove the turn limits on some of the maps - nope, fun-sucked again, need his creator password lol.
This was the campaign he listed as 'normal' difficulty btw, never mind the 2nd which is listed as 'hard'.