no, they are avoiding obstacles, but only those which they should avoid.
I set all stones passable i.e. handled exactly as terrain, they are impassable only if has a very high slope. but of course they could be set as obstacles similarly to buildings trees and bushes (as I did in my earlier tests).
since there's no any c_tracing used for movement it is not desirable to use such a small models as passable because sometimes the unit legs are getting hidden (but the same happens in any Total War game when units are moving on high slope terrain).
@wjbender: thanx, I'll start fighting system soon, and also have ideas for walkable buildings having 1 or 2 floors for seige battles.

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