This is a beta of the new PDF interpreter for Ghostscript and the GhostPDL family. It supports all the same PDF features and output devices that the old Ghostscript PDF interpreter does, but is still missing some "extra" (not required by the PDF spec) Ghostscript specific features - mainly, it currently only supports "resources" (fonts, CMaps, ICC profiles) built into the binary in the romfs (COMPILE_INITS=1), and not from disk.
For this beta, the Windows installers are unsigned, due to the logistical issue with our binary signing certificate - that will be resolved before the upcoming Ghostscript/GhostPDL release.