I am in the middle of a project and controller not responding , cant pause, stop cnc is still moving but at a slow and pausing movements
Your PC might not be meeting the required performance requirements, or have some incompatible hardware/drivers. Try using UGS Platform - UGS its a little less heavy
Still, doesnt matter, do try UGS first, it will help us see what the cause is. But one step to eliminate the software stack, if it still stalls we move on and try the next thing
Something odd I note in the screenshot, you seem to be running the Dec 18th, 2018 (almost a year ago) version. It may be a bug already fixed in the year since (commit log: winder/Universal-G-Code-Sender shows regular commits), so try a newer version please: http://bit.ly/2L2v9k6