Also, when I open a drawing and the drawing is hidden from view and when I move the cursor over elements of a drawing, the element briefly appears and as I roll past the element, the element hides from view again.
I have seen the display completly stop, go blank, disappear. Very dissapointing. The only hint that I can find is 3Dconnexion incompatability and or Windows 7.
Yesterday I disconnected the 3D mouse with success!
Today I grabed the latest NVidia driver, verified the latest 3Dconnexion software. The result is the same. Any touch or vibration on the Space Navigator causes Draftsight to stop the display. Hovering the pointer reveals flashes of the drawing elements. Autocad reported the existence of a not certified 3D device, but it is working for now. AutoCAD had also would blanked out at times.
Workaround is disconnect the 3D mouse and put your left hand in your pocket to stop trying to use it.
NVidia 310.90 Jan2013
3Dconnexion 3.16.1 Nov 2012
DraftSight V1 R3 64 bit
I am now also having this problem. Last week it worked fine, today new drawings & existing drawing elements are not visable unless highlighted.
DraftSight V1R4, Windows XP SP3
I fixed my issue. I couple of days ago I changed my display colour setting to 16-bit. I changed it back to 32-bit and now DraftSight works again. Pretty silly bug.