Hello Vouk, I work for this project. We had a similar issue with other plugins. The problem occurs, when any external plugin changes the applications global language settings. Because we enumerate the the plugins at startup, the expected default language is then broken. This has been worked around for the upcoming Vegas releases, but not for the older ones.
To fix this, make sure not to change the application wide locale setting (setlocale() or similar). For further support, feel free to drop me a private message/email.