unitool, thank-you for access to your map. Everything I have looks identical to what's in your map, but if I create a TP in your map it still only teleports me, and not my rockets. If I clone your TP, everything works.
The only thing that strikes me as different is that your trigger_multiple and my trigger_multiple get painted with a different texture in the 3D view:

On the left is a unitool one, and on the right is mine. As you can see, the "Textures (in use)" box also displays two different trigger_multiple textures.
All I can think is that I'm going the wrong way about inserting my trigger_multiple. These are the two ways I've tried it:
1. right-click, select "triggers", then "trigger_multiple".
2. create a box using any texture (caulk), then select it and change it into a trigger_multiple as in 1. above.
Do you do it any differently?
Thanks for any ideas anyone has.