Cross Section Curves Help

Hello all,

It’s me, again. My apologies for all these questions, but I have been trying to teach myself Rhino from these Lynda courses. Right now I’m trying to make cross-section profiles (white line) with my current blue curves. However, it’s not working. I tried exploding and joining the closed curve, but to no success. I checked the direction and tried all variations, but still no dice. Can anyone help? I’m not sure what I’m doing wrong. Any advice would be greatly appreciated.

help.3dm (3.0 MB)