Actually the MWE may help:

\usemodule[simplefonts]
\setmainfont[KFGQPC Uthman Taha Naskh][features=arabic,range=arabic]
\setcharacterstripping[1]

\setupdirections[bidi=on,method=one]
\setupalign[r2l]

\starttext
\tfb

الْحَمْدُ

\stoptext

—MHB

On Fri, Apr 29, 2016 at 5:52 AM, Mohammad Hossein Bateni <bateni@gmail.com> wrote:
Thanks, Hans!  The problem is almost fixed in the latest beta, version: 2016.04.27 10:18.  I didn't think something had changed in the past two weeks; that's why I hadn't tried with the latest version.

There is only one word where I notice bad placement of diacritics when using CONTEXT.  Compare this and this.

BTW context gave the following "warning" about not being able to access the data.  Is that because it was the first run of a new installation?

system          > lua > compiling '/Users/bateni/context.newest/tex/texmf-cache/luatex-cache/context/5fe67e0bfe781ce0dde776fb1556f32e/fonts/data/names.tma' into '/Users/bateni/context.newest/tex/texmf-cache/luatex-cache/context/5fe67e0bfe781ce0dde776fb1556f32e/fonts/data/names.tmc'
system          > lua > dumping '/Users/bateni/context.newest/tex/texmf-cache/luatex-cache/context/5fe67e0bfe781ce0dde776fb1556f32e/fonts/data/names.tma' into '/Users/bateni/context.newest/tex/texmf-cache/luatex-cache/context/5fe67e0bfe781ce0dde776fb1556f32e/fonts/data/names.tmc' stripped
fonts           > names > accessing the data table failed

—MHB

On Fri, Apr 29, 2016 at 4:42 AM, Hans Hagen <pragma@wxs.nl> wrote:
On 4/29/2016 5:01 AM, Mohammad Hossein Bateni wrote:
The attachments in the email below were too big for the list (>100KB).
I uploaded them here <http://mhbateni.com/context/bug-01/>.

On Thu, Apr 28, 2016 at 10:20 PM, Mohammad Hossein Bateni
<bateni@gmail.com <mailto:bateni@gmail.com>> wrote:

    Hi,

    I am not sure whether I'm missing certain features in the font
    definition or whether there is actually some bug in how CONTEXT or
    LuaTeX for that matter handles this font.  It might as well be that
    there is something wrong with the font
    <http://fonts.qurancomplex.gov.sa/?page_id=608>, though I doubt that.

    Attached is my simple test program and the PDF output, which is
    annotated to show the problems.  You can compare with the reference
    PNG file I generated via rendering in Chrome.  I hope you can see
    the annotations where I have pointed out the incorrect typesetting,
    otherwise you can compare the two outputs to notice the difference:
    for the most part, some diacritics that are not placed in the right
    location (both vertically and horizontally).

    I am using Mac OS X with CONTEXT current version: 2016.04.13 16:46.

can you check the context + beta from the contextgarden?


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