I am playing a solo Austria campaign, and have run in some fairly minor points.
One turn I got the message "Charles de Lorraine" is now active. When I zoom to the place (by hitting the line) I go to Wien. He isnt there - I take considerable time to look him up - at the end of the log it is mentioned that he is placed in command of the army. That is where I find him. This is a bit confusing.
Some turns later I get the message that Leopold von Daum is promoted to form a new army. I had sent him to the eastern flank, commanding a independend column. Now he is 3 star, but also back in the west of Austria, leaving my column uncommanded. It might be better to leave him in place when promoted.
In early march of 1757 the Colonne d 'Alsace is released. The Alsace can not be entered yet. As a result the Colonne d'Alsace cant travel though Alsace and needs to travel along the east bank of the Rhine. (You can also not remove a move by dropping the force back on it starting point - they may not enter their starting point. This can be solved by using <delete>, but had me puzzled for some time). It seems more logical to give the Alsace region free the moment the first troops get active.
When moving the reinforcements from Wien to the north, I could not enter Krems (North of Wien, and connected by road and a bridge) directly. The troops insisted they had to travel by way of Korneburg (nort-east of Wien, also connected by road and a bridge) and from Kroneburg to Krems. (Weather was good, not other complicating factors). No big deal, but it took the troops another 7 days of marching - and they are needed near Prague!!
And finally - more text would be usefull!! As it is the only way to find that a region has become "playable" is to try it - or by inference when the troops get active. Sometimes there is a "red" line (Like when Russia enters the war), but more consistent use of this (or of popups for the more important events) would be nice.
On a related note: it would add to the immersion (my immersion at least) when the message "this region can not be entered in this scenario" could be replaced by "this region is currently neutral and can not be entered". The former gives the impression that the region will stay unenterable for the rest of the game.