Boolean Difference Using Curves

Hey everyone, first time poster here.

I’ve attached an image of my project I’m starting to work on. I’ve imported line work from AutoCAD, which is represented by the pink lines. All I’d like to do is extrude these curves downward three inches and use boolean difference to create an imprint in the gray solid I’ve also created.

Boolean difference fails each time I try to extrude the curves by -3 inches. Is there anyway to accomplish this? Perhaps an expeditious way to fill in the interiors of the polygons using solids so I can then complete the boolean difference?

Provided image: https://i.imgur.com/JWxrZXp.png

Best,
Thank you.

Hello - please post a file with the curves and the target object, I’ll take a look, or send to tech@mcneel.com, with a link back here in your comments…

-Pascal

Rhino Model.3dm (107.6 KB)

I’ve attached the Rhino Model through this post.

Hello - you’ll need to clean up:
image

then Join the curves into closed curves - make sure with SelClosedCrv - and then extrude from the Solid menu.

-Pascal