I wonder if this a similar problem to what I ran into using the TMSAdvOfficePager a few years back. It is recognized as a tab/page control but, because of the way it is built, the individual tab items are not accessible using ClickTab, even though the ClickTab method was available.
What I ended up having to do (and I can't find the info at my finger tips) is utilize some of the native properties and methods of the control rather than TC's helpers to actually sort through the list of available tabs and set a "current page" property (or whatever it was called) to that tab. It wasn't exactly a "clickTab" but it simulated the effect.
Not being familiar with your specific control, I can't give any more than that.
BTW, if you're not already familiar with this page, check out
http://smartbear.com/products/qa-tools/automated-testing/survey/It allows us users to give feedback to the SmartBear folks to say we'd like to see support for different control technologies. Might be worth adding your request into this.