I used AutoCAD, but (I think) you can also clean up layers in Partmaster. Go to "View/Layer Gallery" and turn the lights on or off by clicking on them. Choosing "Hide all except this layer" is fastest to see i ndividual layers. Make sure the lock is UNLOCKED on the chosen layer after choosing so you can work with the layer. When working with layers and things just are not working, ALWAYS check to make sure it is unlocked. Saves a TON of frustration.
Once you have a single layer showing, you can see what it has for data/geometry. If it isn't part of what you need to work with, at the least turn it off and lock it, or delete it if deleting won't mess you up. If you need the layer for something else in another program, you can always save the partmaster revision as a new/different/revised file.
The air cut was the omision/addition of a "-" in your Z depth. I haven't made cuts yet, so don't know if the "-" is needed for Dolphin. Some
CAM programs use the - in Z depth, and some don't as "depth" implies a Z going down. Probably the best reason for buying Dolphin is I can settle down and deeply learn just one
CAM program now. It was kind of fun (like a puzzle) learning each
CAM program (Feature, Master, Pro-E, Bob), but if you can't legally use them for something you might actually hope to sell some day, the time becomes wasted and better used for other productive things.
(Have I really only been playing with Dolphin for a week and a half? Very intuitive)