How to put the argument in the URI path

Views Date range seems to be the perfect module for what I'm trying to achieve but I think I miss something.

The site is for a theatre that has archives that span for many years. These years are split in 2 seasons, Spring and Autumn.

What I'm trying to do is to create a View where 2 arguments would give me the shows for one season, like www.example.com/shows/2009/spring would give me all the shows that happened between January and June 2009. Or else, anything that would allow me to get the shows by season.

Obviously, the node type has a date field. Setting the "year" argument is easy to do without Views Date range but for the time being, let's forget about it.

I created a View with a single argument that splits the year in 2 - january to june and july to december - each with its own label, "spring" and "autumn". This is what I get:

www.example.com/shows/2009/spring: all the shows from 2009
www.example.com/shows/2009: all the shows from 2009
www.example.com/shows/spring: no sorting, all the the shows from all the years
www.example.com/shows/spring/2009: no sorting, all the the shows from all the years

I think that what I miss is how to pass the date range argument in the URI.