During a search for obscure online HyperCard materials today, I came
across a document on the 'Legacy Docs' section of the Apple website. It's a
FAQ-style page for some changes to HyperCard 2.0, but there were two
specific parts that I thought might be of interest to this group.
Part 1, regarding the HC file format (I wonder what would happen if you
contacted them today asking for information!)
The HyperCard file format is available for licensing on a case-by-case
basis. Since HyperCard has moved to Claris, developers should contact
Claris for more information if you feel that your product is a substantial
and important addition to HyperCard and the Macintosh.
Part 2, which just made me smile:
With the introduction of HyperCard 2.0, many of the old bugs were quashed,
and absolutely no new bugs were created. In fact, the software was so
bug-free that it immediately attained Nirvana and Apple has had problems
getting it to do anything since. Just kidding.
The full document is available at:
https://developer.apple.com/legacy/library/technotes/pt/pt_15.html