Thanks a lot for the report, we weren`t aware of this - as it`s a first report of this issue.
To confirm, to reproduce this, we do the following
1) Create an army with workers and enter View Mode (field combat)
2) Do something with workers for them to get bugged? What exactly though? - fighting, looting, gathering? And how do you tell the bugged worker unit apart from normal units?
3) Transfer these bugged units to the homeland and move them to the healing well - results in a crash.
I`d greatly appreciate if you could provide more information for step 2.