Software flawed and support slow and incapable

I bought the Software 2 weeks ago and am very disappointed in a number of ways.
The "Cut video" function is not working. The video is jerky so strong that you can not work with me. The answer of the support: "Edit Video" mode, I could also cut the video. I should try it. So is well accepted that some functions are not run.
"Edit Video" mode, I was able to first create a new project and add 3 videos and somewhat awkward cut. So far so good. When I re-opened but the project the next day, the jerky from the 3 part video existing project also so enormous (about 1 image every 1-2 seconds) that it is absolutely not to use and continue editing.

All other support requests has been answered with absolutely not targeted responses and response times of up to 5 business days anything but timely.

Therefore, I will now return the Software because I have in the meantime helped me with the Windows Movie Maker. Namely I took the video for this weekend and could not wait any longer.

By the way: On my hardware it can not lie. Quad-core 3.2GHz, 6GB of RAM should be enough ...