A question or 2 about UK roads

[AntonyVW]

On the route Im building I have a 4 lane road - 2 lanes going one way - 2 the other, commonly known in the UK as a dual carriageway. At one end of the road it combines to form a standard 2 lane road and at the other end it splits up so that it can join (or leave) a roundabout. This is a fairly large roundabout so a few meters between the entry and exit roads. My first question is how do I combine the dual carriage way to form a standard road going from 4 lanes to 2 lanes without losing the traffic? And obviously with that splitting from a 2 lane to a 4 lane using all 4 lanes?
Secondly how do I maintain 2 lanes of traffic going to the roundabout and 2 lanes coming off the roundabout to join the dual carriageway?
Are there any roads available that can achieve this? Or am I going to have to do something more complex?

I hope Ive made sense.

Antony

 

[klambert]

I strongly suggest you download one of paulzmay's Bridgehampton routes and look at how he's set his roads up: just search 'bridgehampton' on the DLS.

 

[AntonyVW]

Thanks Klambert

 

[AntonyVW]

Having now looked at paulmayz route I guess that using the ajs road system seems to be the only option. I had hoped there might be a less complex way of doing this. Oh well time to study.