[Plugin Connections] alphaindex for a single category?

I have one category that is very large; the others are smaller.

I would like to use the alphaindex ONLY for that single large category.

When I use the short code:

[connections show_alphaindex=’true’]

It brings up everything in my directory, even when I have specified

[connections category=2]

Can I specify a category in the alphaindex short code? Do it some other way?

Thanks!