I have checked and rechecked everything.
language system entry for arabic is there.
all init medi and fina forms for lam and alef are there.
all anchors are set.
the features are generated automatically.
I exported the file as OTF and tested on Windows 7, Indesign 2018 (with world ready composer) and the font is behaving oddly.
Only the letters in “Basic Shapes” category are being displayed correctly, all the other shapes (all letters under “Basic”, init, medi and fina) are being completely ignored.
I added customParameters of “unicode ranges” in font info.
In InDesign, all marks are “fatha, damma, kasra etc.” are also not showing.
and entry and exit anchors are also not working.
I tried the font in MS Word 2010 and everything is working just right.
I experienced a similar problem when opening and updating an Arabic glyph file to Glyph app 2.6.5 (1342).
As a result, the ‘Lam_alef-ar’ ligature does not work (after updating the OT features).
If I remove the part of the lookup script, then it works.