David,
If you have multiple controls in a child panel, but you want to scroll only one of those controls (the canvas) when the user scrolls the panel, your best solution is to place the control that you want to scroll in its own panel (a grand-child panel, if you will). You can size this panel to be exactly the height of the control, place a horizontal scroll bar on the panel, and hide the panel's frame and titlebar. Then, when you load this panel as a child of your other panel, it will look like a canvas with a scrollbar, which sounds like what you want.
I'm attaching a .uir file with a panel like the one I described (it's in 7.x format. Let me know if your version of CVI is older than that, and I will save it in an older format)
Luis
NI