According to this knowledge base article, certain RTF tags are not supported in the Crystal Reports viewer.
At the top of the article, it notes "Version 7". What does this indicate? Is the document up-to-date?
Are there any plans to expand the support for RTF tags in text objects of Crystal Reports?
Would this be a bug for which we can open a ticket?
Apologies for the rapid-fire questions, but I need to know stuff in order to keep going forward on this portion of the project