Technical problem in creating compound glyphs. Assuming I have all the Combinig Glyphs, both FontForge and Glyphs build them easily. For the uppercase ones, I create the corresponding glyphs, in the two programs with slightly different names (same name with capital letter for FontForge, same name with .case suffix for Glyphs).
Let's assume, however, that I intend to create a diacritic without Unicode encoding, for example the breve sign for Cyrillic, with a design other than the Latin breve (sure, it is not that in Cyrillic there are many letters with the breve and it is possible without too much effort to do everything by hand ...) I can call this glyph .breve.CYR, or any other name.
At this point, it seems to me that neither program recognizes the name and is able to construct automatically the compound glyph. Am I wrong or is there an effective technique? Thank you