Visual Circle Slider not working online


I cannot seem to get my slider to work online. I created a visual slider in builder where I made the slider variable derive it’s value from a separate circular objects’ size. So as the slider is dragged, the circle gets bigger or smaller and that value is my variable.

I based this off of the new slider demo in PsychoPy (by setting the size parameter of the marker to “pos.markerPos, pos.markerPos”; and put this in code component preceding the marker “pos.markerPos = 0”, in Begin Routine).

When I put this online, the error that I receive is this " * unknown position units: use prefs"

Would really appreciate any help at all!

Thank you!