The model should be up-to date - see Top-Tips, below.

The model may not be up-to-date.

To make sure the model is up-to-date - especially for complex models:

1.Click Rebuild Now

2.Click to disable Auto Rebuild, and then click again to enable Auto-Rebuild.

3.Move the Master-Machine-Angle to 0 (Do ALT+H (Run menu > Home)).

4.Edit a Part, then exit the Part-Editor. This also rebuilds the model.

5.If there is a 2D-Cam in the model, open then close the 2D-Cam dialog.

6.Click Rebuild now.