After spending most of the day debugging why Arabic shaping is broken in the luaotfload, it turned out to be an attribute issue. The first allocated attribute by \newluatexattribute is 0 and ConTeXt code don't seem to like that, it specifically expects attributes used in luaotfload to be < 255 and > 127.
The problem didn't show before switch to luatexbase, so I expect there was some change in how \newluatexattribute allocates new attributes. Also, to avoid any other hidden surprises, is there a way for luaotfload to assign attributes in the aforementioned range in a way that works nicely with the attributes package? Regards, Khaled -- Khaled Hosny Arabic localiser and member of Arabeyes.org team Free font developer
