Good question! But I think the topic and the posting is misleading! I thought you were talking about your "Walking foot" until I read the post. But you really meant your foot pedal migrates across the floor!
I have tried shelf liner, no success.
I have tried double sided tape... it quickly loses it grip.
I am wondering about building a fence for it and screwing the fence to the floor?
Anyone have any better ideas? I'll buy it if you guys say it works!