How to configure Flat Rate Shipping in a Category

[VIPER7]

We are trying to configure one of our categories to apply a flat rate shipping rule but have been unsuccessful in our attempts.

We have tried setting up a new warehouse, associating that warehouse to the product in the category, yet in the checkout, the shipping is showing $0.00.

Any help would be greatly appreciated. TIA!

[VIPER7]

Ok, to further elaborate on the issue we are experiencing, we wish to charge a $4.90 flat rate shipping method on EACH product ordered inside of a particular category. We CAN get a single $4.90 shipping charge to display in the cart, no problem, but when multiple items ordered from the same category are placed in the cart, it is only showing 1 charge of $4.90 for the entire order on not for each item. We do have the "Shippable" property / option set as "Separately", which I believe in theory is what we want, it's just not behaving that way.

Any assistance is greatly appreciated!