Let us pretend, for a moment, that I'm a total idiot. With no programming experience beyond following someone's nice instructions to get BAT to load automatically. Who maybe actually had to look up how to get a DOS window to open in Vista because she forgot about cmd. Done? Great.

Sooooo I'm trying to follow someone else's nice instructions to change the commerce increments, which consist of "in the XML file, go to global defines and change 'commerce change increments' to whatever". I... can't seem to do this. I search for globaldefines and I open the result in Notepad (although it seems to be a .ini file, which, again, idiot, that isn't the same thing, right?) and I can't #$%^ find "commerce change increments" and the file seems incredibly short anyhow. When I try to open any of the files that result from a search for *.xml I get an IE window with an error message about opening XML with an XSL style sheet.

So, going from the premise that I'm at the bang the rocks together stage of technological advancement, could anyone just tell me, from step one, how to do this? From, like, "turn on your computer"?

Humblest thanks.

The GlobalDefines.xml is in the Civ\TheAddonYouPlay\Assets\XML folder.
You have to open it with a right click, then edit or open with Notepad or Wordpad.
And then you have to change this entry:

<Define>
<DefineName>COMMERCE_PERCENT_CHANGE_INCREMENTS</DefineName>
<iDefineIntVal>10</iDefineIntVal>
</Define>

to the value, you want to have.

Thank you, sir!