Hi Dawn - the cut extents of the file loaded into WAM can be found in a few different locations:
First is in step 2 of WAM, under Scale and Position. The scale of the file can be increased/decreased and will affect the width and height accordingly. The ratio is locked though, so changing the width but not the height is not possible, and vice versa.
Second place is at step 6 of WAM, under Cut. This gives a brief overview of the resources required to complete the cut. In order to get an overview, the cut quality and material must be selected prior.
When it comes to nesting, manipulating the location of the origin will likely come in handy! The forum post found here goes over what the origin is and how to place it in the ideal location. It can be difficult sometimes due to cut bed condition!