Allow spacer-only, with counterbore screw hole

[fx]

👋 Pretty new to openscad, looking for feedback on this one.

Instead of printing 1xN w/ a spacer on one side, I wanted to just print the spacers by themselves to allow for some variation and add text and other customizations on the spacer itself.

When grid x/y is set to 0, this uses the padding width to create screw holes through the padding. It also allows half of the hole to be counterbored if that setting is enabled. Meant for distancex < 41 of course, has no effect on the grid (e.g. try distancex = 80 and gridx = 0 -- can't imagine that's useful for anyone.)

Could this be done cleaner/differently, or is this approach okay?