I have a couple of answers here. One, I have the Corel V-10 as well as the V-9. Don't buy the 10 Version just yet. Corel released this product way before it should have been released. In fact, the program looks like a Beta 1 product, full of problems. I would suggest holding on to your current version and watching the forums to see when Corel comes out with the patches for this. I am very, very unhappy with it (as well as many others). I can't believe Corel would do this to the many great users out there.
I have a Logitech mouse with dual wheels on it, as well as a button that allows you to zoom in and out, or set the window to scrolling. Take a look at the control panel under your mouse settings. There should be a program installed there by the manufacturer that will allow you to make adjustments and change the settings to your preferences.