I just discovered this issue the other day. I'm running 7.3.37 on Windows 10.
I load up the render queue (still images or XRs) and hit Process Queue. Whatever is the first job in the queue completes no problem. But then KeyShot clears the queue without actually rendering any of the remaining jobs. I haven't witnessed when it actually happens, I just check back and the queue is empty (I remote desktop to this machine).
I'm wondering if anyone else has had this happen or if I just have something weird going on. Sometimes I am using two of our KS licenses, one on my local machine and one on the remote desktop.