[Imp]

Okay shouldn't comment without at least looking, I couldn't resist. Resisted starting as the situation looks fluid so will require some thought. From looking at how I am deployed I would guess this has good replay potential.
This may need some play testing & special victory conditions, based on how many forces you exit.
Fighting withdrawal is in my book one of the hardest things to do well, so I would expect quite high loss ratio.
Also some of the bridges are stone I would suggest making them all wooden.
May also wish to create a different set of stats for the engineers demo charges that have a better chance of destroying bridges, not a certainty.
Some or all could carry a placed charge, best switched off at start possibly.
Suggest increase the property that destroys bridges & reduce the others, AP I am guessing.
So high AP low HEkill & warehead
Reasoning is a placed charge if done correctly should direct its energy at the target, any blast that goes elsewhere is wasted energy so it should be minimal.
Hence small blast radius, a good demolition is contained & relatively quite as all the energy is absorbed by the structure.