It's been reported before. I think it's because the language.dll you have in memory isn't the correct one. I'd suggest a re-boot and then a re-install if the beta.
reboot & reinstall did not fix it. I had to delete c:\program files\newsbin folder (64bit) before reinstall... and I made sure I backed up everything this time before doing it
did not change any language settings... English should be default. I am running win7 64bit if that helps and installed 64bit Newsbin version. I had to delete C:\Program Files\NewsBin folder and removed Newsbin.bin from AppData folder to force install, kept all other files in AppData, then after install copied back original Newsbin.bin and that clear the issue I had.