Bad driving on Five Ways roundabout Birmingham UK - Van driver cutting into lanes

This is almost an everyday occurrence on my commute to Birmingham everyday.
People are incompetent at driving and fail to understand how a spiral roundabout works.

Van enters round about in left lane to do almost full circle right hand side exit 4th exit - incorrect lane.
On approach to 3rd exit van then swerves into middle lane - incorrect - spiral roundabouts are intended that no lane changes are required if you enter in the correct lane.
Van driver insisted on winding his window down stating I was in the wrong for entering his lane - as you can see this also is incorrect

This type of driving happens constantly on Five Ways round about in Birmingham no mater which way you approach from.
Poor signage and poor driving all constitute to making the roundabout a nightmare specially at busy times.