Got the new build of Calibre, works almost spot on, except I kinda screwed up and didn't realize there is a forced 5px border on the left and right, making the usable width 590 pixels, not 600.
EDIT: And again, I don't do enough research. The PRS-900 tells the Reader software what it's view rectangle is with the capabilities.xml file. Looks like the 900 has a 584x978 usable area for things like ePub. Playing with the Calibre source for profiles, it seems to be spot-on too.
Last edited by Kolenka; 12-28-2009 at 05:25 AM.