Using LogMeIn app with participant screen share

OK, I've been able to create some training classes without much trouble.  (Many hours spent watching Alistair Lee).  I've run into a snag with the setup in my class.  I"m having my students log into

remote computers that host some machine training software.  They're using LogMeIn software to do this.  In Connect, I set the permisions to use presenter screen share and everything works fine.  I can watch what they are doing in the remote computer.  The strange thing is that, after I stop the screen share, my students computer screen goes black.  It takes a CTR-ALT-DEL and logout-in to fix the issue.  

Anyone ever use a setup like this?  I susptect the issue is with LogMeIn.  Any recomendations on other remote login software that might work?