UPSX: Episode 2 credits:

Leo - mapping work and retexturing/conversion work, additional scripts, additional story
Jack Honda - additional mapping work and textures, story and translator messages
UnrealGecko - initial work on e2l1b and DMU version of Dragoncastle
Yrex - additional texture 
Nikola - additional fix
Delacroix - additional translator message (E2L2)
Lightning Hunter - provided new Nali skins.
3, BaratusII - testing
Turboman for the psxbat - might have been credited before but what the heck - "this was actually a discarded pawn from FireStorm that he gave me. - Leo"

Alcapowned for reanimated Human meshes, initial Jrath pawn and his animations (for e2l8).
Teridax for Jrath mesh itself.
QTit for misc. scripts earlier on in the developement, reused for specific stages of jrath, etc.

Original map authors:

Jakub Kisiel for E2L1.
Jeff Rubin for E2L2.
Matthew Kagle for E2L2D, E2L6, E2L7.
Mike Bastien for the cut PS2 DM-Gutter (reused as part of E2L2D).
Elya Iceking (Ilya Isaykin) for E2L3, E2L5 and "hibernator demo".
Jason Watkins for E2L4, E2L8 (part).
Nathan Silvers for E2L8, E2L9(and 10 but became part of 9).