[NTG-context] ConTeXt minimals: Issue with file.iswritable and 'Cg'

I use contextgarden.net/minimals/ and the following problems showed up after an update. a) file.iswritable(cachepath) failed. The directory is writable for the user but not for others. I have not debugged why it failed. Affected file: tex/texmf-linux/bin/luatools b) bin/mtxrun failed at line 5013: Somehow my lua(tex) did not digest the Cg: protocol = Cg(V("letters"),"protocol") * P("://") + Cg(Cc(nil),"protocol"), tex/texmf-linux-64/bin/mtxrun:5013: attempt to call local 'Cg' (a nil value) Any ideas? (I removed the readable check as work around and changed the Cg to P as quick work around.) Tobias PS: I use Fedora 6, which is the dated but centrally installed Linux here.