OK to have a set of double doors that each slide open in opposite directions, you need to do as I’ve done in the screenshots, you’re welcome 
I will try and get a video tutorial up soon showing how I (eventually) managed this! (Manim8 on YT)
Although seen as this post is from 2016 I will assume you’ve solved it, but for anyone who is still looking here for an answer, here it is!
You need to set up ONE Timeline, with 2 Vector graphs inside it. One for each door (DoorSlideR and DoorSlideL). Then enter the transform values as appropriate. Also have a Variable set up for each door with the Open value stored in it. From the Timeline, use Setters to set the new locations. Then put the Event graph together as below.
