Hi,
used font:
http://fonts.qurancomplex.gov.sa/wp-content/uploads/2012/06/UthmanTN1-Ver10.zip
Minexample:
\definefont[uthm][file:UthmanTN1Ver10*arabic at 20pt]
\starttext
\uthm
\setupalign[r2l]
كَلَّآ
\stoptext
You see, that the letters are not connected, it should be look like
the attached image with this ligature.
In the image you see the same font and the same above unicode-text,
but rendered with CorelDraw instead. So it may or may not be a
font-issue, but solvable in ConText?
Thanks.
Huseyin