I bought and downloaded the app yesterday on my iMac.
My main problem is that even after reading the other threads and doing the recommended things, my computer audio is not being recorded. I have the latest version of Voila and VoilaDevice. I have tweaked my sound settings and nothing helps. My mic and visuals from my computer come out fine though. I'm mostly trying to record skype conversations and games.
Other than that, I've had problems recording extended periods of time. After recording for 20 or so minutes, Voila refused to pause+save, pause, or cancel the recording. No matter what I did it continued showing that it was recording, until I force quit the program, which made me lose the video. After recording for 40+ minutes, it crashed my computer. I've had this computer for three years now and it's only crashed in this way twice, so I'm fairly certain it was this app. My computer is custom-built and very powerful. I don't know why I'm having all these problems.