Hey Rob,
Check out the addmesh() command.
I had the exact same situation as youself with Binman (loads of road sections) adn wrote a routine that created a mesh and surface and added all road sections to it to become just one mesh and one surface - but i am told the addmesh() command does this for you!
If it doesn't work out for you with addmesh() give me a shout and i'll send you the code from Binman to do it.
Check out the addmesh() command.
I had the exact same situation as youself with Binman (loads of road sections) adn wrote a routine that created a mesh and surface and added all road sections to it to become just one mesh and one surface - but i am told the addmesh() command does this for you!
If it doesn't work out for you with addmesh() give me a shout and i'll send you the code from Binman to do it.