Some good news for you... Pad++ and Dynapad are in a decently runnable state again! Myself, Jim Hollan, and Tom Gillespie have been on and off working on refurbishing it.
Currently, there's still a good amount of rough edging from the mzscheme -> Racket rewriting, and support is primarily for MacOS and Linux.
Going forward, there's a lot of modernization to be done. In particular, Racket-on-Chez no longer affords escheme.h, so there's a lot of inversion of control to be done. I'm also working on and off on an updated multi-platform rendering layer to largely replace Pad++'a X Windows drawing, with the goal being to move more of Pad++'a logic up into the Dynapad layer in Racket.