hello ! What a wonderful pièce of software ! I suggest you provide with an export module to Construct 3 sprite font. https://www.construct.net/en/make-games/manuals/construct-3/plugin-reference/sprite-font
Check for Spacing data
Inspiration may come from https://www.construct.net/en/forum/game-development/tools-and-resources-27/sprite-font-generator-v3-64038
Look for exported files.