Basically, in each non-clockworks-Grand-arsenal-Soldier-graveyard-HoH room, when you open up the options, there would be a box with it saying this:

Set room as spawn

Once checked, elevators and login will bring you here instead of the Haven spot you've normally been spawned into. If you leave, the box would appear like this:
Current spawn: Town Square [change]
Once you click change, the spawn will change to your current location.
There will also be a [Don't use spawn] checkbox. This will ignore your spawn options.

This works on GHs and all parts of Haven.