The lookup flag controls what glyph stays on the baseline. Glyphs sets RTL flag by default for RTL glyphs so the rightmost glyph stays on the baseline, without this flag the leftmost glyph stays on the baseline (which is the desired behavior here), but AFAIK Glyphs has no way to change the lookup flag for cursive anchors.
In fact in arabic script we need vertical kerning but our friends in glyphs denying this
I’m not denying it. I would never do that. I might be a bit slow understanding and adapting in some cases.
We did work on this together and I implemented it some time ago (in Nov 23). You can disable the lookup flag by adding a “.LTR” suffix to the anchor name. So in this case, use “exit.LTR” and “entry.LTR”. It might not be the most fitting terminology (and I’m open for suggestions to improve this).
I missed that you already implemented it. That would be a better solution for the OP issue.