not sure if this has been mentioned lately, if at all, but during any skirmishes i have played since two or three patches ago (i.e. the patch that introduced the IS3) i have encountered the following problems:
1. wehrmacht does not ever build the building allowing for panzer 4, panthers, ostwinds. this occurs on every map and every difficulty.
2. soviets never build any tanks they (assumably) buy an upgrade or something in the tank hall and nothing further happens with regards to production once the progress bar is filled. happens on every map and any difficulty