Magic number offsets are also replaced with named constants.
Merlin 16+ increased the label size from 12 to 26 at some point and the 15-char limit causes duplicate label errors on some Merlin source code.
I regenerated the pre-compiled toolmacs file based on GSBug's toolcall list (plus Marinetti toolcalls).
This includes new tools from system 6.0/6.01 and a a few name updates. The _DU is gone I don't know what that is offhand and I dare say nobody used it since it doesn't exist.