I tried playing this campaign (as either hero), and I didn't encounter any particular difficulties. I really liked the first mission, but the second one has a problem that I don't know how to solve – every time the creature week is announced (new creatures appear on the map), it starts to glitch terribly – I have to replay it several times to find a situation where the map remains stable – it doesn't crash and allows me to save. The first time, when the third week was announced as the week of Furies, the map crashed only once; and the second time, when the 6th week was announced as the week of Salamanders, I had to replay it eight times until I found a stable situation (and it turned out to be far from the best possible – for the last two days, I didn't move three out of four heroes from their positions); the 9th week (which is also supposed to be a creature week) simply doesn't start – the map crashes for the 10th time in a row :(
Here's a link to the save file where the game got stuck:
http://hdd.tomsk.ru/desk/nhqceksc#
Unfortunately, I can't upload it here – the size is too large.