I believe you need to have fixed locations, as you mention.
Possible workaround is using reinforcement cards, were a player(s) is not allowed to use it. (AI will use it btw, so it works for SingelPlayer) Combined with Automatic distribution this should work.
Edited 1/11/2015 17:37:21
- Through this is based on trust, of course... You might want to make it public whenever someone plays a card.
- If Players start with more then 1 territory, the cards allows him/her/it to freely place the armies, (e.g 20 on one, instead of fixed 10 on each. Other players start with 5.)