Wrench events.
Make a 1x12x5 (Or whatever brick(s) you want) brick, hit it with wrench. Click events, give it a description. Now make a trigger brick, and give it an event called "trigger" and enter in the group box whatever you entered in the description for the 1x12x5.
Hit the garage door brick with the wrench, open events. Now make a new event called "Wait For", and click "trigger". Now make another event called "Door". When the door option pops up, check Invisible and No collision. Also, make the door events time for around 25-30(00) MS.
