Hi, thanks for getting back to me. I should have made clear that this is not a laptop touchpad, it is built into a PC keyboard. The manufacturer, Trust, don't do a custom driver for it at all, they just use the generic Microsoft mouse driver. (They were quite surprised that I thought there should be a custom driver, when I asked about it). This is also true of another touchpad for PC I have bought recently, from Jelly Comb, and many budget laptops. They work just fine with the MS driver, including multi-finger gestures and so on, but on some level Windows thinks they are mice, and so doesn't provide the tab with the touchpad configuration options.
It makes lots of sense for manufacturers to use the Microsoft driver rather than having to provide their own, in many ways it's easier for everyone, but unfortunately the Win 7 one at least is not well-written, and by the volume of people asking for a solution (but not getting one) on Microsoft's support website, it's a common problem, and also an issue in Win 8 and possibly 10.
I am buying touchpads for my PC because arthritis in my thumbs is starting to make it difficult for me to use a mouse comfortably. The PC is running a clean install of Windows 7 Professional 64 bit and is a year old.