Btw, I couldn't find this information in any of the documentation...I scoured for hours!
One question: I tried an alias that merely had "wedge" in the name, but it didn't seem to work. Only assigning "wedge" (exactly) to the Alias field seemed to work, but I can't rule out that some other setting was incorrect when trying that way. I also named the custom driver "wedge" just to be sure (in the Name field). But maybe this isn't necessary?
If anyone else has this issue in the future:
In Kstars go to:
Tools > Devices > Custom Driver
Then you can select an existing driver and assign the "wedge" alias to it. Then be sure to select the new driver in your custom profile.