Version information:

ConTeXt  ver: 2016.04.30 18:59 MKIV beta  fmt: 2016.4.30  int: english/english
luajittex, 0.95.0 and luatex, 0.95.0

running on Windows 10 x64

Error message:

error: ...eXt/tex/texmf-context/tex/context/base/mkiv/font-otj.lua:1205: attempt to index local 'i' (a nil value)
tex error       > tex error on line 7 in file C://Users/rik/Desktop/comp_body.tex: ?

Code:

\setupdirections [bidi=global]
\definefont [hebrew] [default] [lang=heb,ccmp=yes,script=hebr]
\definefont [Hebrew] [sileotsr*hebrew sa .9]
\starttext
 \startparagraph
  Hebrew : {\Hebrew רִ}
 \stopparagraph
\stoptext

When the first line is removed, or the value of bidi changed to on, no error is thrown.

A single-font version of the code, for fonts that have Hebrew glyphs, fails with some fonts (libertine shown below), but works with others, for example, dejavu sans.

Code:

\setupdirections [bidi=global]
\setupbodyfont[libertine]
\starttext
 \startparagraph
  Hebrew : רִ
 \stopparagraph
\stoptext

My installation, or is this a bug?

--
Rik Kabel