The above is not quite complete, some things are missing or
underdocumented. The code that drives the prettyprinting is in the file
<tt>buff-ini.lua </tt> (which is called by <tt>buff-ini.mkiv </tt> and <tt>buff-ver.mkiv </tt> from the TeX side), in the ConTeXt distribution.
If you're missing anything, you'll probably find some answers there.
Don't forget to write down what you find on this page!