Our main tip to users when importing a dwg-file in Vectorworks: DON'T SCALE THE RESULT!!! 🙂 Hatch definitions won't scale and might become ridiculously dense. That will make your graphics card run extra hours.
During training sessions we very often have to explain the best way to import a dwg-file.
If there's an issue with a dwg-file, this is not a scale. It is a unit issue.
1. Open a blank document with your units.
2. Import the dwg-file as if it was drawn in you units. Do not use the detected units, they will be wrong. AutoCAD users never indicate the unit they use to work.
3. In the result, check a dimension or size you know. I.e. if you see a staircase, the stair width will be something like 80cm to 100cm, sometimes 120cm. If it reads '900' units, that means the dwg-user has been thinking in mm. If it reads '0,9', his units were meters. DO NOT TRUST DIMENSION OBJECTS IN A DWG. They may be 'exploded', what makes them just lines an text.
4. If the units in your imported file don't match your settings, THROW AWAY YOUR CURRENT FILE AND OPEN A NEW ONE. Don't just throw away the imported objects sibce the hatch definitions will stay in the file and they are already too dense...
5. Restart the import in a new, empty file. But now use the units as you found them in step 3.
Succes!