Currently, I have a set of save game files where I have Grand Armee II sitting in Hannover with 18 divisions in it, and a Swedish army is quite predictably attacking every single month (stupidly, since it is massively outnumbered, and immediately retreats once detailed combat begins). However, every time combat begins, my Imperial Guard division shows up as a "reinforcement" and detaches itself. [:@] In an attempt to work around this bug, I have detached 6 infantry divisions from GA II (leaving it with only 11 divisions), and then attempt to attach only the Imp Gd Then, 100% reatably every month that I try this, Sweden attacks from Hannover and the Imp Gd detaches itself, yet again.
I would love to here some acknowledgement of this bug by WCS, or better yet that a fix is on the way in some upcoming patch

I'm tempted to simply disband the offending division, since it is worse than useless anyhow, but it'd be nice to find some way to make it work.