AbleCommerce Shopping Cart Software

I created a zone and a flat rate that is only assigned to California.. This works fine and only shows to California customers.

I now want to limits California to only this flat rate option.. I have tried multiple things and it always breaks something.

I went to UPS ground for example and selected all zones except this special California zone and when I do that it does not show as a option for California customers but it also does not show as a option for anyone else.
So if "all zones" is selected it shows up for a california customer and a ohio customer
But if "selected zones" is selected and I select all zones except the california one it does not show up for anyone.

I don't suppose many people have tried this but what the heck am I doing wrong here..

If I select all zones it works as I would imagine
If I select a single zone it works as I would imagine
If I select multiple zones it does not work as I would imagine

It is almost as if the code is not set to process through multiple zones when specific ones are selected

Maybe I'm misunderstanding your set up, but I tested some.
I have a zone for Ohio, another one for all but Ohio.
I have a flat rate that applies to Ohio zone only.
UPS Ground applies to all but Ohio zone.
Ohio address sees the flat rate only.
Illinois address seess UPS ground only.

I don't have any zones configured for the other US states and just a few shipping methods since this is a development site. Maybe there is some overlap somewhere in your configuration?

Thanks for taking the time to help.

Can you try adding a few more zones and selecting multiple zones for one method and see if that works as expected?