Hello John,
There is no way to add tokens to the control. If you want to use custom object, you have to create a custom token with the desired information, and use the CreateTextBlock event, to replace the standard token with yours. This approach is described here: http://www.telerik.com/help/winforms/editors-autocompletetextbox-creating-custom-blocks.html.
Alternatively, you can just store your item's text and desired color in a simple dictionary, and use the formatting event to pull the value from the dictionary and color the box as specified:
I hope this helps.
All the best,
Stefan
the Telerik team