One question about the Cossacks: They "ignore forest terrain melee combat dice reduction" but because the rule only says "FOREST" I suppose the rule do not apply with Orchards & Vineyards nor with Walled Gardens? I'm just surprised they can fight in a wild forest but not in a clean vineyard ... ?! On the other hand the Walled Gardens (and not the Orchards) are say to "have all the characteristics and effects as a forest terrain tile hex" so the Cossacks would be able to ignore the dice reduction toward this fortified place and not toward the tender Orchards & Vineyards ... ??
In selfmade scenarios, there should be no problem, to use scenario rules, which class the vineyark/orchard terrain with the forest rules for Cossacks.
I would not allow the "Cossack" rule with walled terrain, because "walled" is a higher-value cover and hindrance than only woods/orchard terrain.
In official scenarios there is still a different gameplay, maybe also because of simplicity.
But i will ask Richard, what his original intention was.
To conclude the Cossacks would follow all the normal terrain rules so would reduce minus 1 die when fighting toward of out of a Orchard & Vineyard and would not fight after entering a Walled Garden. On the other hand they would ignore combat dice reductions only with pure FOREST were they can:
1) Enter inside a forest and still combat!
2) Ignore any combat rule while fighting out of a forest!
3) Ignore any combat rule while fighting toward a forest!
I was on the Walled Garden - OK that the Cossack cannot attack when they arrive on a Walled Garden?
Finally Richard confirmed, that the special "Forest" rule for Cossacks apply to forest only,
also if some other terrain have a low level hindrance than a forest or a terrain would refer to forest (as a walled garden e.g.).