The message clearly said you should have a Couatl.err log file in your %APPDATA%\Virtuali folder, that would be the only information we need to understand what that error means, and it would have taken far less time than making an uploading a video, which we kindly ask if you can remove it, please.
So, let's start again: what's inside your %APPDATA%\Virtuali\Couatl.err file, that the error message said to check ?