I accidentally discovered a redeployment bug i am submitting.
CSA -> Civil War scenario
I wanted to redeploy one of the 1861 spawning generals from Richmond to Knoxville and i am posting this immediately so i don't forget

Procedure:
1) Select 1861 general after moving him out of the stack and select Redeploy.
2) Scroll on map, where's Knoxville now? (Tabs still list richmond stacks)
3) Select 1st Reserve Bde tab (Supposedly disengage 1861gen Redeploy)
4) Click somewhere on map
5) Look at 1861 general, Redeploy order greyed out
6) D'oh...1st reserve BDE (still locked!) got redeployed.
If i hadn't such short memory as to where i had wished to redeploy that general, i would have never found this out.

I guess it's then possible to exploit this to redeploy any stack. I didn't check but the aforementioned procedure is correct and if a locked unit could be redeployed, perhaps any stack size can be redeployed with this trick. On the other hand, i noticed (to my expenses) that if i redeploy clicking on region, the redeployment happens but if i click mistakenly on a stack in that region, the redeploy fails while still being burned out (like it had been successful). In small regions where many stacks are present this problem is a killer.
More on Redeployment: I think inactive generals should not be allowed to redeploy at all. Actually, i would LOCK the entire stack of an inactive general so the human player can't exploit the detach-from-inactive and then use all stances of an independent forces which is something the AI can't do (this is a true exploit actually).
On the other hand i agree with the redeployment as a concept. It is currently working with Leaders and with HQ (and thanks to this bug with other unit types basically).
In general it would do with small units and i couldn't see a better extension of this order than the one allowing us to also use it with those units we build in all states.
Specifically:
Eng
Nav Eng
Medic
Signal
These are all administrative/small units that should be allowed to redeploy. It makes sense because just like leaders and HQ they are small-sized units and they are often needed in a completely different place from where they are spawned.
I would also add the Marines. Why?
It doesn't make sense to build them in N.O. when you need them to assault Ft. Monroe. At least with Redeploy you can use them next turn.