cuteTube uses the same API as OVP, so it should use the same number of CPU cycles to play the same video. The backend used is gstreamer (I don't have any control over this).

Scrolling will be affected whilst the video is playing, as the video playback is using up CPU cycles. There's no way to avoid that, other than to remove the feature. That's the approach that Nokia themselves took with the stock player by not allowing video playback to continue when the application is minimized. They took the view that it's better to maintain performance and avoid user complaints of 'lag'. The only way to have your cake and eat it is to throw more hardware at the problem.

I have taken a small step to reduce the number of CPU cycles used when cuteTube is minimized during playback. The progress bar and position label are now updated less frequently (every 10 seconds, like the stock music player). It doesn't make a huge difference, but it's better than nothing. The change is included in the update that is awaiting QA approval.