I've installed IDEA Community Edition 2016.2 and fecided to start from fresh confituration, so before first run I've removed configuration from 2016.1.
When I start IDEA 2016.2 first time, it shows first dialog "maximized", but only upper-left corner is drawn:
After that, it shows properly-sized dialog with theme selection, and after that it hangs forever, but consume ~1 CPU core all time.
I could kill idea64.exe process and after that it starts in "Default" configuration. If I remove its configuration folder, process repeats.
My system is Windows 7/Ultimate/x64.