After you've imported blue print and traced ...

[jbhk]

Two parts:

Once you have imported your blue print and traced the walls, can you get rid of the background image?

Can you coppy your walls only into a new file? I'm trying to use the original plans as a starting point to place and plan a guest house on the same property, so I need to enlarge the file/project to accommodate the land/lot size, not just the residence size. Is there a way to do this?
Thank you

[Puybaret]

You can hide or delete the background image with the menu items of Plan menu.
You may copy/paste some items of the plan between opened documents and if you want to enlarge the plan, just drag an item of the plan to the direction where you want to enlarge. As soon as you’ll get close to the border of the plan, it will enlarge by itself.