I have recently updated to Autodesk Inventor 2018, and now Draftsight crashes when I try to open a .dwg

Previously I had Autodesk Inventor 2016 and Draughtsight with no problems.

• Windows 10 64 bit

• Graphics and software all updated, including Draughtsight.

The only way Draughtsight will run is if I do a repair install every time, and have Inventor closed.