I've had an occasional crash but not all the time. I know Mr. VincentSun is working right now on an update to the Waylens Suite again and should be ready soon/hopefully.
One issue you may be having is the transfer rate in Mb/sec might not be fast enough for the read of the USB drive. Normally the USB drives don't have that fast of transfer rate for read/write. Especially for HD video. That is probably where you are getting your errors and bottleneck from. You PC is plenty fast.
You may try transferring your video files directly to your hard drive on your PC, then work with them from there. Samsung makes a small SSD external USB drive that is very fast you could buy one of those and use that.
Samsung T3 250 GB is very small and very fast.Superfast file transfers with its 450MB/sec read-write speed. Not 100% certain but they have up to 1 TB capacity depending on models. The 250 GB is around $100. BH Photo Video, Best Buy, etc..
Also you could get a small micro SD card/USB adapter and pop out the memory card from the camera and put it in the adapter and read the data directly from the card and work with that in Waylens Studio. ..as long as your read speed is fast on your SD card. If you don't have fast enough micro SD card for write/read speed you are going to get corrupt data, same with your USB drive.
I had a USB drive on a ATSC digital converter box to record broadcast HDTV from antenna signals and I tried several and none worked. I'd get glitches and skipping and freezing. When I switched to fast SD card and USB adapter it recorded perfectly with no glitches at all.
Hope this helps some.