I've been using DraftSight 2016, the free version, on Windows 10 for 11 months with no problems.  Today I paid \\\$99 for the upgrade to Pro.  The upgrade appeared to work on version 2016.  Next I installed DraftSight 2017.  When the installation was done I clicked "Finish" and the installation wizard tried to start the program.  Windows immediately popped up a box with the message, "DraftSight has stopped working".  I tried to start DraftSight from the desktop icon, no luck, same message.  I tried uninstalling it with the Windows tool, then reinstalling it.  No luck.  I tried that again, rebooting after the uninstall, no luck.  I tried uninstalling using the Draftsight installation executable, rebooting, reinstalling.  No luck.  I tried one more time with a complete power down in-between un-installation and re-installation, no luck.  I have tried installing it as both the free version and the pro version, it doesn't work either way.  One interesting thing: the installation wizard already knows my license key for the Pro installation.  That implies the uninstall doesn't wipe that information from the registry.  Does this mean I cannot do a true "free version" install because the key is still there?  Could I have been given a defective key?  Is there a way to check that?  I'm out of ideas, and after paying \\\$99 I have no working version of Draftsight.  Ideas please!

Later - I was able to reinstall DraftSight 2016 and it is working.  Whew!  I'll hold off on 2017 until the bugs are fixed.