Does Cubase work well with video? If I want to write music to film/tv - Can I then run the video in Cubase 8? And it will have the features I need to keep time/frames with the video material?
Or do I need a 3rd party program for video scoring?
There is an extensive knowledgebase article on video support in Cubase but you should be aware that Apple no longer provide security updates for QuickTime for Windows, on which this support currently depends. If you’re on Mac you should be OK.
In Cubase, you can load a video into its own track and it is usable for scoring, but you can’t subsequently export the video combined with the audio – you have to render the audio, and find some way to remux it with the video. This is something many of us have asked to be addressed in this feature request.
Im sadly on Windows 7 
What are my alternatives?
Do you know any other DAWs? That supports video without Quicktime?
Reaper.
Well.
It looks like Steinberg made an official post saying that would look for another program that doesnt involve Quicktime.
Hurrah to that!
Cubase works great for scoring-to-pic, I use it regularly. However, I highly recommend converting to an MPEG H264 codec, I found that is what works the best with Cubase.
I really hope Steinberg adds the ability to export a movie file along with embedded audio, like Logic X.