Style Children not working

[Asilouhuette]

I've modified the default style templates a bit, and now I have created a child style of the default style for use with specific forums. I changed it so the forums I want will use the child style, and the rest will use the parent style.

Now, despite my best efforts, I cannot get any changes to only apply to the child style. I always click the expand button on the child style when trying to only edit that style. I have tried only having the child style checked before clicking to edit the templates. No matter what I do, changes are applied to both templates and I can see the changes on all forums.

The template I am editing is SHOWTHREAD. I would like threads to show differently on these specific forums. I DO have the correct style selected for each of the forums in the forum manager.

Is there a trick to this that I am missing?

Thanks