If you can use the other options than waiting for us to check win 7, please do it. I cannot guarantee timeframe we get to it.
Or if you have some time you can try to debug jsreport.Local code.
We start the jsreport.exe process somewhere here
You see we are removing some strange environment variables which likely VS adds.
It was causing some issues in the past for the jsreport.exe
It could be that there are some other strange environment variables your system is passing and we may need to remove them as well.