After a long delay and numerous startings and postponements, I'm glad to say the SandMath Manual is finally done - and posted at the usual site.
http://hp41.claughan.com/file/SANDMATH_44%20Manual.pdf
It finally got to the point that I didn't remember exactly what was in the module, specially after adding the secondary FAT and the sub-functions - so I needed the manual too!
Won't win a Pulitzer prize but if you're interested in the SandMath then it'll be a great reading. Personally I think it's at the level of the 41Z Manual, hope you also find it interesting.
Cheers,
'AM