Nope. You don't have to be from the US. It helps if you pay and it will also lift your download limit. If you have bought any Stardock product, that download limit is lifted too.
Even if you don't have the registered version of WB you can make skins for it. But it helps if you have the registered version, because that doesn't have any limitations.
I hope you will enjoy your time here, scubabliss. We have a help and skinning forum if you need any help (see the top of this page). There are Stardock newsgroups too if you need some serious help.
Cya around.
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