World Height Discrepancies?

I have a landscape material that blends multiple layers based off of Absolute World Position and slope angles. When I design or play within the editor, the elevation levels are right where they’re supposed to be. When I play the level as a standalone game or press simulate, those elevations are way off. In 4.4.3 this wasn’t happening, but since I cloned the project and opened it with 4.5.1 this is all of a sudden a new thing. I am just curious if anyone else is having similar issues. Why the discrepancies?

Here are a couple of screenshots to illustrate my issue. Notice the grass layer:

Editor / PIE Preview (Correct Elevations)

Standalone Game / Simulate (Not Correct)

Any help would be greatly appreciated!