At what point can curve resolution be adjusted? I have my model all drawn out and just learned about this parameter. Is it too late to increase resolution for an export to print?
You can change the number of segments (I assume that’s what you mean by resolution) in a circle or arc up to the time that it becomes entangled with other geometry in 3D. At that point, there are unresolvable issues of what to do with the connected geometry if you were to change the segments in the arc, so SketchUp discards the circle metadata and just treats the arc as a polyline.
Keep an eye on the Measurements Box at bottom right of the UI.
Notice when you first enable the Circle or Arc tools you can set the number of sides (segments) prior to creating the geometry.
Or, immediately after creation by entering a value followed by the letter ‘s’, say, 48s, via the keyboard.
Later on, you can edit Segmentation and Radius via the Entity Info dialog.
That is, until as @slbaumgartner says, it becomes so entangled with other geometry the Segments and Radius fields are grayed out.
Well that is way easier than holding down the control key and hitting “+” a bunch of times! Er, uh, I mean I have a friend who has been doing it that way!