@abbaspour: That's because there's a specific target for the older devices (kindle-legacy) which enables some more trickery to tame down the TC. Also no real guarantee that everything works properly on devices without a touchscreen, hence the lack of official release (cf. kpdfviewer instead)
Note that this was last tested with a fairly not-so-recent MG toolchain, it might not be enough for a bleeding edge TC; see the comments in the
Makefiles.
And that my own tests were made (again, long ago) with a TC built against glibc 2.9, so, I obviously never ran into that one

.