First go to the BP_SmartAIComponent then in the My Blueprint panel search for the Min Follow Distance variable and delete it as it is not used. Next search for the Follow Distance Dead Zone as again it is not used.

Once done compile the BP_SmartAIComponent and save then close the project.

Then download the files linked below and unzip the files. Then navigate to your projects main folder (This is the folder that contains the Content, Config and Saved folders) once there drop in the downloaded folder you unzipped. You will be asked if you want to replace the files, click Replace the files in the destination.

https://www.dropbox.com/s/p590mfp9x4dwhj3/Content.zip?dl=0