Claus is right in all his replies, but I feel I should add the following to muddy the waters a little.
In WMA the fall back rule was amended so that you could only move to behind your own battle line. Moving forward with a fall-back move I don't think really threw up too many complaints, but the most common use of the move in my experience at least is when you have a draw, and in this instance it always seemed rather odd...
As to towns. Well, obviously as with all terrain consult with your opponent ideally before even deploying terrain, or if you have fixed terrain (say at an event), then prior to deployment. Unless the town in question is exceptionally large (say more than 20x20cm), then it is in my experience usual to treat the whole thing as dense terrain. So visibility restricted to 2cm, impassable to everything bar infantry, and obviously stands being attacked count as defended for shooting, drivebacks (one less dice), and of course for the first round of combat.
Another alternative, especially for very large urban areas is to treat sections as dense terrain, with one or two roads passing through as open terrain to allow cavalry to pass through, or artillery to be placed, etc... If you really want you can also intersperse a couple of fortress towers, impassable large buildings and so on. I actually think that it would be really interesting to fight a very large battle with at least half the map made up of a huge city, it's walls and the area inside it. That would make for a great demo game at a Games Day if we could both pull enough resources together for it and find a GCN club for us to run it under...