Ruler changes on offset path (809)

OS X 10.10.5
It displays one value when I hold cmd+alt+ctrl, then when I press M to enable it, the value on the left gets smaller and a little dot appears…

The offset value is 11, 10, Make Stroke, No Autostroke, 50%

I can’t reproduce it. Can you send me the file?

anything yet?

Sorry for not answering. Your file works fine for me. Can you try to disable all plugins?