you know when we create a new character are the kern value & metrics will change or just stay or need a new add metrics & kern?
If replacing a glyph with a completely new design, you will need to adjust or recalculate metrics and kerning adjustment pairs.
maybe i need to follow this trick maybe? Changing Kerning and Metrics for an Existing Font
also, i agree for that and it looks perfect, but if there is much a new characters it was hard