1. On 25CC (dotted circle) move top anchors to the right, they should be over the top dot.
2. On 25CC (dotted circle) move bottom anchors down to bottom line and to the right.
3. Add 'kern': gemination & 25CC = −660
4. I really dunno what to do with 25CC+subjoiner. But because it is a virtual virama and should not be in normal text, I’ve just moved subjoiner’s anchors down and to the right. Maybe you’ll coin a better way.

(OpenType is so fragile, hope I did not affect any of font’s functionality.)