Multiple enemy jostle with wall collisions

Around a year ago someone helped me out a great deal with getting multiple enemys to jostle for position and head for the player.

In this basic example they are heading for the mouse, but the same rules apply.

the problem is the enemy to enemy and enemy to player collisions all use radius calculations to keep them apart and stop overlaps (collisions).

Can anyone suggest how i can include a robust wall collision detection into this routine?

a semi working example can be found here… (hit F5 if they get stuck)

and here is the CS4 source…

Would be SO grateful if someone can suggest a good way to deal with these multiple wall collisions, so enemys will navigate around the walls and continue to head for the player once they are round them?

Ive been playing with “point detectors” which ive used in AI car games in the past but they dont fit with the other collision method used??

PLease help!

Many thanks in advance andi.