Is there more to do with bignums besides https://github.com/jmoenig/Snap/pull/2602 or do you mean help screens?
re: help screens: I've updated all my rendering code to Snap! 6, which was surprisingly easier than expected. I still need to write a script to separate all the strings from the layout XML, like Jens wanted, as well as some overall cleanup.
p.s. If Jens is reading this, I'm liking all the behind-the-scenes changes in Snap! 6. 
Oh! And I even commented on the PR two weeks ago. My memory is really going. Thank you thank you.
As for help screens, one thing I'm dreading is that we really have to hyperize the ones for scalar functions. I'm hoping the block-specific part can all fit in the gray part, and we can have a generic baby-blue part that talks about hyperness. I think you should delegate that task to one of our current crop of 12-year-olds and supervise. ;~)
What blocks are these?
Easiest to explain by starting with non-scalar functions. Those are the ones whose domain includes inputs that are necessarily lists, things like ITEM and MAP. Scalar functions have simple inputs such as numbers or text strings. (Functions with functions as inputs are a third category.) In 6.0, scalar functions can be extended to lists: (3 4 5) + (12 14 16) reports (15 18 21) i.e. (3+12 4+14 5+16). Same with lists of lists (matrices).