Can it be done without using the transition list script, which does not work for me?

Maybe try using a logic_playerproxy; it sure has something to do with the portalgun.

Why not just put down a portal gun entity with only the blue portal enabled?

1. Tried playerproxy already. Has no such options.
2. The player picked the blue portalgun up in the map before.(It's a mappack)

BrainstoneX wrote:
1. Tried playerproxy already. Has no such options.
2. The player picked the blue portalgun up in the map before.(It's a mappack)

soooo, player has a normal gun on him... then you want him to pick up a blue gun... and this is not the start of a map?
ONly other thing i could think of is have a weapon strip trigger. Maybe put it around where you want them to pick up the gun. then on trigger, disables the strip trigger, and picks up the gun.
edit
they in a elevator.. so just strip that weapon, and have them pick up the gun above that trigger.

Here's what I did:
1) Place a thin trigger_weapon_strip at the floor of the elevator, make sure kill weapons is set to yes.
2) Place a Portal gun next to the ceiling inside the elevator, make sure you check the flag to make the portal gun immobile.
How it works: When the player starts in the elevator, the trigger_weapon_strip will get rid of the portal gun. As the elevator moves up, the player will acquire the new portal gun and the trigger_weapon_strip will be inaccessible. The reason why you can't put the Portal Gun above the elevator is because it will stop the elevator from moving.

Scripting is the easiest way if you are dealing with multiple maps.

(Edited of course)I read the question wrong to myself. Sorry...