There are a lot of options but typically, if you create a datum point along a straight edge, it works without trouble. It uses the plane of that edge at the point's location to determine the projection (unfurl) plane.
It takes a little getting use to and it does make assumptions.
There is also a flatten quilt dedformation to keep in mind. If you need to add planar references, you can add them in 3D using this command.
For your work, this is worth getting some practice time in.
Lots of discussions on the web and here. A good sample... how to develop this?
If you cannot get it to work, just add a rough part file here (full version please!) and we can take a look. You can attach files in the advanced editor.