Thanks Mark.
I found the underlying MathMap code is excellent. It's very stable with multi cores and lots of ram. Composer seemed to be a logical place to do animations.
Of course not all combinations work together but I'm sure there are mathematical reasons why they don't. I now have a library of Composer combinations that work very well.
It was a revelation to see that almost all MathMap filters can be animated when combined with animated filters.
I am attempting to build a Windows10 version of MM on Windows. The gegl 0.3 patches from 9 years ago no longer work and Gimp now uses gegl 0.4.
I think the obstacles can be overcome. I'm using some of the mingw-64 packages which is like a Linux packaging system for Windows.
All the best
Tas