Yes, I played it, but it's not one of the most interesting activities.
First, on the second visit to the cave, you need to play cat and mouse with "The Law."
Then, you have to wait a month near "Andragor," or spend about a month running around, and if you enter the cave three times, "that friend" will be there again. :)
In the end, I spent about 12-13 days in prison.
As for the breakthrough, it involves running to the "mentor" and into the "peaceful" cave. There are also advantages; I was already level 37 (+ 2 skill trees and a quest that gave me an almost unbeatable 40) on my 6-7 month (Veteran Mage) playthrough, but then I still had to gather some more troops for the mausoleum. The map was completed in 204 days.
Also, I'm thinking of playing Heroes of Might and Magic: The Eastern Expedition this weekend.