Hello Dave. I am glad to know that the "3D" work challenge isn't "just me".
As to Aspire and its relief layer organization, it uses a component tree, which is really quite different than the Aspire 2D layer manager, or any other layer managers I have used.
The Aspire component tree does appear as a stack, with each relief component having its position in the stack. Each component can be changed by itself as to being in add mode, subtract mode, merge high, merge low, thus controlling how each part will combine with the other parts in the component tree. And each part can be moved up and down in the tree, which can also affect how it interacts with other parts in the model.
They also provide for easy organization of the component tree by allowing the user to gather lots of loose parts into "groups". A group can then be copied and set aside for later access, while the original group can be "baked" into a single relief component (at which point all of the constituent elements loose their ability to be individually manipulated, which is why you need the back-up "copy group".
But the Aspire relief modeling organization seems to be pretty well laid out and almost intuitive.
Thanks, Chuck
Chuck Keysor (circa 1956)
PRT Alpha 60" x 144" (circa 2004)
Columbo 5HP spindle
Aspire 9.0, Rhino 5