During testing earlier font versions; it reacted perfectly with Indesign & illustrator justifications sub-menu;
Choosing between ME Single Line & Every-Line composer, works fine.
I am unable to figure out what has gone wrong so the paragraphs are getting no change in terms of the above mentioned Tatweel options.
(today I’ve updated to Glyphs 2.5.2 (1149) but I’m not sure it is related to this version)
I believe we had a similar issue before. And IIRC it was related to glyph set. Are some arabic letters missing or have you expanded a lot of non-Arabic? I would also look into the code pages and Unicode ranges parameters in Font Info > Font.
I wish I am wrong with my conclusions;
It seems that automated Tatweel does not work when a font has multi-levels of connections based on Entry/exit anchors !
However Manual Tatweel (Inserting Kashidas) does work !
I very much hope that someone can refute my assumption on this form