As far as I can see in the game code, the communists should be able to come to power through civil war. To do this, it is necessary not to assemble a coalition after choosing the democratic path in Germany. However, the event that leads to the further continuation of the game in this case does not work, since all these events have a # icon. If you remove it, the events simply break down. Maybe the path has not yet been finalized...

In addition, the communist path cannot be chosen for Germany in the game lobby.

However, the game has a DDR tag, and you can transfer to it. At a quick glance there is nothing interesting there