You are right. HyperCard 2.2 or HyperCard 2.3 does not print color, nor is it likely to in the near future, because as you mentioned - color is added in as an XCMD and not fully supported in the body of the application.
Color printing is not a trivial task and would require a great deal more development time to implement in HyperCard.
Article Change History:
02 Jan 1996 - Added HyperCard 2.3 information.
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