Forgot to mention I'm using an old version of PaintShop Pro for the graphics, and don't have Illustrator.
I made a mistake, in that Imagine3D could only import 2-colour images, where it would treat black as solid and white as transparent. So something like this:
... which you can import and treat as an object (for extruding into 3D, etc.). Can you at least do it that way?
Otherwise, is there any way to convert a bitmap image to a vector one?