The way you're picking geometry is the problem.
First go to Other>Contour and shift select your geometry chain. If the whole chain doesn't select, stop and fix the problem. Usually a gap, untrimmed entity or double entity.
This will give you an arrow which indicate the cutter direction. If it's wrong, go to Utilities > Reverse Contour. (don't ask why it's not in the same dialogue box as Contour).
Then you can select the contour as your profile geometry.
You can shift select your chain without using contour, but it's difficult to tell which direction it's going.
If the above doesn't work, post your file. It's probably a geometry problem.
Good luck,
moldmker |