I just tested NX 8.5.3.3, the next MR (Maintenance Release) which is planned to be released near the end of October, and it seems to work fine. That being said, you are of course aware that what you're asking is actually a two-step operation and that it's not something which is controlled within the sketcher itself, correct?
To activate the option to 'Make Objects Off Work Plane Non-selectable' you have to first toggle ON the 'Work Plane Emphasis' icon on the 'Utility' toolbar. Only then will the 'Make Objects Off Work Plane Non-selectable' icon become active, at which point you can now toggle it ON.
Now this is a change of behavior from earlier versions of NX, but note that once you've toggled ON both the 'Work Plane Emphasis' icon and the 'Make Objects Off Work Plane Non-selectable' icon, you only need to toggle ON/OFF the 'Work Plane Emphasis' icon to control both behaviors.
Anyway, give this a try and see if it works.
John R. Baker, P.E.
Product 'Evangelist'
Product Engineering Software
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
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