Area chart - categories and brush (mini graph)

[HughProctor]

I have 2 area line charts both using same data source & data; one is a mini chart.

The X-Axis displays categories, such as "Microsoft Business", "Microsoft Premium", etc and other products.

I need the smaller graph to use the Brush function to be able to Select (selection) and manipulate the bigger chart.

This works fine when the categories are numbers but not when categories are text.

In order for the categories to change to display the category text I have found I need to perform an updateOptions call, which stops the selection brush from working.
I've attached two images - one with selection function working the other with the x-axis categories (labels) but selection not working.

Any ideas? Thank you in advance