Expert rules for UK region in Seeded e business tax patch

Hi All,

We have applied e business tax seeded patch in our Instance, I found that some expert rules were created for UK region tax setup. and all the tax setups were done at 'Global configuration owner level'.

Now, as per our client requirement we don't want to use that seeded patch and wants to do all the setups at Operating unit level.

Could any one please tell me what is the purpose of those expert rules?, is it mandatory to create those expert rules? and

Please suggest me on, how to create expert rules?

Regards
Keerthi Kanth