Ores should only overlap minimally. If it fails to acheive that it won't generate the patch at all.
I'm guessing if you have increased size of patches allowed overlap might be slightly bigger since it uses percentage for that.
I'm not sure what do you mean by difference between regular and infinite iron - there is no infinite iron by default. Setting for Angel infinite ores will increase the infinite patch part in comparison to whole patch.
Yeah it's for Angel's. I wasn't sure if that was more of an RSO question or not since they work together. There's a setting to change the % of the infinite per patch so also having sliders confused me.