Sometimes I'll get toolpaths (using Multi-Axis Machining) whose internal options become locked. This is separate from the entire toolpath becoming locked (like via the right click menu). Text boxes I seem to be able to right click on and Unlock (see image), though I have to do them one at a time (see image).

Drop-down menus appear to be totally immune to this fix, however, and right clicking them does nothing whatsoever. Hovering over them will provide this highly illuminating tool-tip at least. I take great solace in such wisdom.

When this happens the only solution I seem to have is to re-make the toolpath entirely. I've tried making a new copy, but the problem comes along for the ride. Locking and unlocking the entire toolpath does occasionally fix it, though I can't find a correlation on when this will or will not be the case.