I have almost the same issue.
My problem is that when I try to export a C2 project to HTML5 with the minify script option it gives me this error message:
"Error during export: Cannot open file
(pathtoexportfolder shows a normal path, witch I didn't want to type in for security reasons - It only contains letters and numbers, and it points to an avaiable drive)
The interesting part comes in, when I try to export on my notebook, with has the same OS and software installed (even the versions are identical) and it works on that machine.