I have ViaCAD so I hope I can help you.
Are you drawing way off to one side of the origin by any chance (Menu > View > Show Axis, if not visible)? If so, press one of the following keys ( a,s,d,f,g), so that the view changes until nothing is visible.
Right click the mouse and select Zoom All – you **should** have something onscreen now that can be rotated and zoomed etc.
Remember that it’s possible to draw a couple of items 0.01mm in size that are 999999999mm’s apart, so they’re easy to lose if you’ve zoomed out a long way!
Keeping things close to the origin gives an easy reference to aim for when panning and zooming.
I’ll send you a PM so you can email me a test file if you want.
Martin.