Problems getting custom ligature anchors to work

We are trying to add new marks to some ligatures for the mark 2 ligature feature. The ligature we have for testing already features top_1, top_2, bottom_1 and bottom_2. What we need additionally is center_2, but we also added center_1 after center_2 did not appear in the exported OTF file. Still the center_x anchors are not exported, but the top_x and bottom_x anchors are.

The test-glyph for this is dotlessbeh_hah-ar (link goes to the Glyphs-file on GitHub).
The OTF exported from Glyphs, that should (but does not) feature the anchors and the mark2liga feature for it is also on Github. There is a mark2liga feature, but the center anchors are missing. The name of the exported dotlessbeh_hah-ar in the OTF is uni066E062D.

What are we missing?

The liga anchors where only implemented for top and bottom. Not you can use any anchors you need.

Now that’s a pitty.
I guess I will have to hack my way around this :-/

here is a version that implements it:

Oh, great, thanks! I’ll have Kourosh check it out.

Thank you very much. This is working for us!