.ZGR File Extension
What is a ZGR file?
Groove file created by BeatSlicer and BeatCreator, which are tools that allow users to slice beats to manipulate loops; contains the slicing scheme of a .WAV loop file; does not contain the actual audio data
In FL Studio, select File → Import → Beat to slice... and select your WAV file to access the utility and create the ZGR file.
NOTE: BeatSlicer and BeatCreator are available as standalone tools or part of FL Studio.