Avatars using Final IK's Execution order have their VRIK locomotion settings changed. The two settings that seem affected are the Step Threshold and Step Speed. In the attached gif is the difference between the builds.
Multiplying the step threshold by two and dividing the step speed by two restores the VRIK closer to its original status in game, but then it is incorrect in the editor.
Deleting the Execution order also makes the VRIK act as it does in the live build, but in this set up the Execution order is vital for the avatar to work correctly.