This folder is at:
~/Library/Application Support/Tinderbox/color schemes
This folder ised to hold custom colour scheme files that are then available for use in any Tinderbox file via the Document Settings' Colors tab.
A colour scheme (TBC) file must be stored in the folder with a sub-folder using the TBC's filename. Thus scheme file 'example.tbc' should be added using a new sub-folder 'Example':
~/Library/Application Support/Tinderbox/color schemes/Example
If the folder and TBC filename match, the Document Settings' Colors tab will generate a preview image.
If a TBC is added while a document is open, it is necessary to re-open the app in order that the Document Settings' Colors tab lists the new scheme.
To make it easier for the general Mac user to access Tinderbox's support folders, the Help menu's 'Reveal Support Folder in Finder' option will open the folder in a new finder window.