How to tilt the ground in the rolling ball demo

So I am using the rolling ball project as a default starter project in Unreal Engine 4. I also have added my own maze object (.obj) as a combined mesh into the project and have snapped it into the ground. My goal is:

  1. create a blueprint for the ground. I have created a simple rotation blueprint but I do not know how to connect it to the ground.
  2. my ideal goal is to rotate the ground every 3 seconds or so about 30 degrees back and forth vertically (yaw). What is the blueprint for that?