Reaver should have absolutely no problems with any other Mods, since it is basically a very simple piece of work, to those who understand the code. Basically the Reaver works this way...
On every level up (beyond level 8 or 9 i think), the Kit automatically applies a Level Up to your Second (ie Inactive) Class, which is the Mage. There is a background script that basically LOWERS the level of your second class, 1 level at a time, IF at any point in time during the game, your Inactive Mage class level EXCEEDS your Active Thief level.
So if you are a fixed number of levels behind (ie 12/14, 17/19), SKing the inactive class (up by 1 level to 13/14, 18/19) should do fine to rectify the problem.
Possible causes could be a Mod installed that affects the Kit functionality of the Reaver, which in turn prevents the level up from working properly.
In any case, the Reaver version released in zymisc2 is, to my knowledge, a very smooth ride, unlike the one that Silk experienced in the past (hence its non-existence in zymisc1)