HELP! Crash Assertion Failed Line: 2159 UE4

Hello,

Upon packaging my project and running it via WindowsNoEditor I get the attached error message. I have attached the crash log and it appears to be an issue with my landscape. I deleted my landscape and repackaged to test and the project launched as it should. I have no idea what this error is or how to go about fixing it!

Any suggestions would be appreciated.

Thanks, link text