Here's an example project with the basics - dropbox.com/s/4q45kbokanulfvo/LayoutsAndDoorsExample.c3p
The key components of doors and portals are:
1. Where are you going - Usually stored as an instance variable in the door. This is used to change to the correct layout.
2. Where did you come from - Can be stored in a global variable or an instance variable in the player object. This is used for positioning upon entering a layout
Optional - A second instance variable identifying door pairs if you have multiple doors that go between the same layouts.
3. Active state - A triggered state so you don't "bounce" back and forth between doors. You can use a timer like you had (not recommended), user input (what I had in the example), or offset the destination/spawn location per lionz suggestion.
I use a single object for all doors, considering they are all functionally the same. If you want to have multiple objects for doors, then put them all in the same family and use the family object for your event sheet logic to keep it just as clean.