odd im finding the trainer works great for orcs in the campaign atm.
Win 7 64 bit
Campaign - Orcs
Steam download
EU Version (if that makes any diff)
The only issue with the trainer i have found so far is that if you enable the "Super Unit" on your hero units it also buffs up the enemies health as well until you use Reset Units cheat to get them all back to normal. You then have to re-apply the super unit cheat and then when a new wave of enemies arrive you have to turn it off and then on again (rinse and repeat).
Good trainer though
I would get the same issue in Chaos Rising's trainer, though in campaign it wouldn't be a problem, maybe because that campaign only had heroes to control. Try only using it on the "heroes" and see if you still run into problems.
EDIT: I'm a moron and sleep deprived, didn't see you clearly state using it on your hero units. Nevermind ...
[Edited by SoM, 3/2/2011 2:29:35 AM]