[Out of This World]

Quick question or two:

1) I use flat-rate shipping; is Google's Shipping Weight value required to be ACTUAL product weight, or can I use "1" for everything (like it's set up in Ecwid)?

2) For things that don't have size/color/gender do they just remain blank or is a 0 value needed?

3) Is "Brand" the same as Manufacturer? We have various items from electronics to toys and games. I'm assuming Brand is "Canon" for cameras and similarly "ThinkFun" for toys, etc.? (Not to be confused with Distributor?)