Actually I had 2 problems:
1. on the first start the "performance check" screen stucked.
2. after opening the program and after a capture it is stuck on "generating video files"
Both problems has been solved:
1. For the stucked "performance check" delete the folder "%appdata%\corel\MultiCam Capture"
Upon deletion and restarting the program it is a blink of an eye going through "performance check"
2. stuck on "generating video files":
Open the file "%appdata%\corel\MultiCam Capture\settings.ini"
Set PerformanceLevel=0 instead of 2
restart the program and it should happily record and save your captures.
Note that, while having the problems, I had to open the task-manager and kill the MultiCamCapture.exe to truly exit the program.
Corel support staff added these 2 solutions to their internal knowledge base in case somebody else having those problems also but I thought it would be a good idea to share
