How do I add a VK248 to a VK2100 with ATEN’s configurator?

1. Click on "Select Device & Configuration"
tab

2. Click on "Add Controller or Expander" button on
the bottom left

3. Add devices to VK248 under the device window 

4. Create a control button within the tab of "Create
Viewer & Design" 

5. Input the control command to the button