The problem still exists for me as well. Unfortunately I can't apply jbmaverick's workaround, as I only have one Engineering Bridge Officer and no open slots.
I've been having the problem sporadically - I've yet to be unable to assign ANY officer, but there's always one station or another that won't fill. At the moment, I can't assign my first ever Purple officer, whom I just received. I personally don't seem to be experiencing the 'All BOff Powers Available at the Same Time'…