I'm using RoboHelp HTML v7.03.001. I've never used the "What's This Help Composer" and I was reading help topics today about how to use it. When I go to File > New, as directed in the help, the What's This? Help Project option is grayed out. So I thought, perhaps when IT installed it, they didn't select that option, so I reran the installer in Repair mode and there ARE no options. So how the heck do you get the What's This Help Composer? The help says it's installed with RoboHTML and, sure enough, there is a whatsths folder in my RoboHTML folder, and I can open the composer (Whatsths.exe) from that directory. But it's not available from within RoboHelp.
I believe what is happening to you is that a "What's this" project is generally tied to CHM output. I'd be willing to bet a dollar against a dougnut that your primary layout type is WebHelp, FlashHelp or something other than Microsoft HTML Help.
Try right-clicking the Microsoft HTML Help layout in the Single Source Layouts pod and nominating this layout as the primary.
THEN click File > New and you will hopefully be pleasantly surprised.
Helpful and Handy Links
Yep! When I tried it the first time, I created a new WebHelp project, since it's the first one in the list. So, then I tried it in an existing CHM project, et voila, it was there!