luatex --version zsh: exec format error: tex/texmf-macosx/bin/luatex
It has been reported and should be fixed sortly. In the mean time you can try replacing the binary with the content of http://foundry.supelec.fr/frs/download.php/494/luatex-beta-0.10.1-macosx-uni...
It may have been built for i386 exclusively.
Indeed. The above link should yield a “universal” binary which, unfortunately, I haven't been able to test on PPC, so I'm interested in your feedback (as well as other's!).
2. I could only generate the database and the formats after having set the variables explicitly:
Yes, this is for the moment a feature. As Hans said, kpathsea isn't used any more, so even setting TEXMFCNF is not enough, as its contents aren't always inspected (at least under certain circumstances).
mtxrun --script fonts --list --pattern=pagella Error in lua file loading: cannot open : No such file or directory
No idea about this one, sorry. Setting LUATEXDIR might help. Arthur