Platypus doesn't work under a standard Enhydra roll-out. For Enhydra 2.2.1 a patch must be applied for Platypus to work. This patch can be found at ftp://ftp.pisoftware.com/pub/pi/platypus/ as PATCH_PI_Enhydra2.2.1v1.zip. The README with this patch details the major changes done to Enhydra.
Platypus provides a modified newapp script to create the development directory layout.
Platypus has a modified stdrules.mk, which lives in the Platypus home directory.
Documentation in progress