1) Overall it was fairly easy to get to Warsaw. It seems that the AI puts too great an emphasis on taking Kiev and Odessa, rather than defending its main city.
Also, from what I saw, there are 2 large forces on the Polish side, but somehow I was only confronted with the one in the South. I saw the one in the north, which seemed to threaten Minsk (and therefore my supply line) for a while, but nothing came of it, and I didn't see it afterward, not even as I was sieging, and then taking Warsaw.
2) That might not be specific to this scenario : I moved a force which contained armored trains to a region with a broken rail line. According to the manual this force should take more time, but repair the line as it goes. That's not what happened. On the screenshot : I moved the force from Korosteni to Volynsky (that turned out to be a very bad idea by the way :bonk

3) This is not so much a problem, but rather a question : the victory conditions (on the red side) seem pretty drastic. I had control of Warsaw, and all but 2 objective cities in Poland (Krakow and Lwow I think), and the polish had taken only Odessa, and yet I only achieved a stalemate. Is the only way to achieve victory to take all polish cities ? What was the thinking behind that ? Just curious.
You can find the zip containing the savefiles of that entire game here : http://www.mediafire.com/?2bnza2eejbaven3 (slightly too large for the forum, even at the highest level of compression, sorry). edit : the move order I'm talking about above happened Late July I believe, and the force arrives in late august.