So this is the problem I've run into lately, I started with a G11 (same as G15 without the stupid LCD) and thought the G keys are totally new buttons that don't take up any original keys, but I was wrong. U have to map something to the G keys. Like A or Shift+a or Ctrl+Shift+A etc
Now the G keys with their 3 different sets are pretty good for this. And if you set it up right, and don't use Ctrl or Alt in the setup u can hold one of them down for an even bigger keymap set. Only problem with G keys is it's hard to stick little pictures of what it is for on it.
I bought an X-Keys Pro USB thinking I could map non standard keys to it, such as ? or ? or ü or é and so on, but you can't. You have to set it up exactly the same as you would a G key from the G11/G15. The software also tells the difference between pressing the Left Alt/Shift/Ctrl and the Right one too! So there is no difference there. At this stage the G keys have a bonus over X-Keys due to the fact you can quickly load a new keymap setup to the Keyboard. However the X-Keys has this data hard coded into the keyboard, so you don't need any software to plug it into a new pc!
To keyclone; You MUST use key maps in order to successfully utilize the keypress setup difference in LeftALT+a compared to RightALT+a. Set the keymaps up on each PC and your done. Only thing is this takes a while to setup, so get a pen and paper and start writing what you want to be passing through etc. And be prepared to make mistakes! hehe

But yeah, Xkeys and G11/G15 work with keyclone. Just takes some setting up!

-peej-