Whether you are using a Mac or a Windows computer the process will be the same. You will need to open the Xencelabs Setting application.

The instructions below show you how to set up a button on the Pen Tablet. If you are wanting to set up a button on your Pen or the Quick Keys, the process is exactly the same. 

Before you go any further, you will want to start and then minimize the application you want to add customizations to. 

In this example, I'm going to add Camtasia to the application row and then change the top Center Right button to Show/Hide the Tool panel - Ctrl +1

To open the Settings application, press the top Center Left button.
Then you will want to select (1) Pen Tablet

Then select (2) the "+" 
Find your application in the list, (1) I'm clicking on the Camtasia icon to select it.

Then (2) click on Next
Then (1) click Add
Camtasia is now added to the Application row, (1) you will notice that it is not highlighted.

In order to customize the button on the tablet and have it affect only Camtasia, you will need to select it. 
Select the Application (1) you are wanting to make custom settings to.

The select the button that you are want to asgin the setting to (2).

Then select (3) Keystroke
Once you select Keystroke, the Define Keystroke panel will appear.

You will want to name your Shortcut Key (1) Give it a name that makes sense to you.

Then in the Keystroke Keys (2) you will press the key on the keyboard in this case Ctrl+1 and they will appear in the box.

Then you will need to (3) select OK
You will now see that the Right Button displays the name of the keystroke you created.

Test it and it will now be working for you when you have the application open that you added to the Application row.

You can as many applications as you would like, and customize them in many different ways. There is so much you can do with your applications in this fashion.