I was/am playing the latestest nightly build with the terrain packs and a few other mods.
I too was having no terror missions in my play through. towards the end of the game, i turned off "YetMoreUFOs" mod, and that fixed the problem. i actually think the mod at this point messes up some other stuff as well but cant confirm (houses and grass were spawning inside some of the UFOs)
I turned on Luke's Extra ufos mod instead of "YetMoreUFOS" and that one seems to have no conflicts with the current nightly build it allowed me to do terror missions)
(The commendation/soldier stat diaries mod does not work at all, but doesnt seem to disrupt the game play in any way)
On a side and off topic note, i cant seem to break through the interior of UFOS with my plasma cannons as easily, sometimes it takes 6 shots, and my blaster launcher doesnt seem to destroy the walls inside the ufo as easily as it did in vanilla, is this a byproduct of one of the mods or did they make this change on purpose in open xcom?