Game freezes at overstack unit destruction

[composer99]

Game loads at combat resolution on an attack on Leningrad.

Any result in which the Germans take the hex results in the overrun naval units rebasing to a port in Finland controlled by the USSR. This results in overstacking, causing two ships to be destroyed. However, the "end phase" button does not light up after destroying the overstacked units, and it appears to be impossible to advance the game state any further.

[Divadov]

Yes, I have the same problem, it's a bug.