I just started using the "secret github download" build on my Paperwhite - awesome! I have tons of scanned manuals in PDF and DjVu to test with.
Only bug I've found is that the "Go To" jump bar doesn't work. It's just a thin straight line and touching it doesn't do anything. I'm not sure if you devs are already aware of it or if that's just an artifact of my days-old build. Standard page turns, bookmarks, and Home Screen progress are all working, very slick.
KPVBooklet is very cool too, turned out very nice.
Thanks for this great work!