In order to be able to do hyperlinking from documentation, you must make sure your documentation tab has been defined as "structured". This is accomplished in the UC_OBJECT_DOCU variable in client 0000. Those tabs that start with the @ symbol are structured and will support hyperlinks.
Then when you type http:\\string or https:\\string into the documentation tab, UC4 will automatically hyperlink the entire string.
I'm now disappointed to discover that UNC pathing (\\servername\folder\) does not seem to work. But I guess it makes sense for the product to not assume that the documentation is always being viewed on the same network. This has not been an issue for us because we put most documentation in Sharepoint or other web-based repositories. And if this documentation is extracted and sent to a customer via email, our email client (MSOutlook) hyperlink's UNC pathing.