I had just tried to start a new game and upon load a string of messages displayed on screen that all the custom ores I had previously been using (Leighzer's and such) were not configured in RSO so would not be generated. I back out and go into Mod settings and scroll on down to RSO's section to find no configuration is possible as none of the ores are listed. Any thoughts on why this would occur?

Did you change any of the mods?
RSO configuration tab has no ore configurations - it's in the mod code itself.
My best guess is that you have different set of mods now - if you have a replacement mod for one of previous ones it might cause this (mod name or resource names got changed).

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