0.3.17RC (ISO CRC 4FDF899F), VBox 4.3.12.
At the end of the installation, Firefox offers to start automatically after ending the wizard. It won't start after that, even though otherwise the app works correctly. Attaching debuglog between clicking on "Finish" and cease of activity. There's "CreateProcessWithTokenW is UNIMPLEMENTED!" amongst the lines, maybe it's because of that.