According to the Boris website, this feature is available in "Boris FX" but in actual use it seems to be missing. You cannot change a spline shape track type to "3D Extrusion"
There is, however, a preset in the keyframe library that uses this function and it loads correctly. The preset is located under "Shapes/Picture-in-Picture" and is called "Extruded PIP". It's possible to load this preset, turn off the gradient background and change the spline shape to something else (i.e., from a rectangle to a circle) and thus build your own custom effect, but shouldn't this feature be available directly as advertised?
Did they remove it for some reason and the preset is just a loophole (I understand that FX is simply a stripped-down verson of RED)? Or have I found a bug in the latest version of FX (I have version 9.2)
Anyone out here with knowledge on this or am I the only one who's even noticed (or cares!)?
Well as you have correctly assumed FX does not offer extruded shapes and that you can open a RED preset file that includes an extrusion is an anomaly.
I'll take a look on the web site to where we may have mentioned anything to the contrary regarding support for extrusions in the FX product and ask that this be corrected. Thanks for pointing that out.