If you have gotten shoes that don't go on the feet of V4 correctly, and the documentation for the shoe doesn't have exact instructions on why (e.g. some shoes are rigged "hard-soled" and are just not ever going to bend at the toe) then you need to go back to the vendor.  All the shoes I've done, including the seraphim boots in my freebies, were modeled around a posed foot and won't look correct at zero pose, but they at least go on the foot and look correct when the foot is posed correctly.

My Freebies