Hi,
In our pro version 1.0.7 we have added the option that will allow you to set this kind of of shipping method
In that you have to create 2 shipping method
If user is logged in, free shipping for orders over $50.
with one condition on total > 50
&
2nd condition on user role as customer
If user is NOT logged in, free shipping over $100
with one condition on total > 100
&
2nd condition on user role as guest customer
Guest customer role is added in the version 1.0.7 after your suggestion
