Client saves also ruleset set server settings to desired settings
Client currently stores all the server settings that have value different from the internal default as desired options. This includes those settings that have value changed because of the ruleset level defaults. That does not really work well with changing the rulesets. If one saves the desired settings when using civ2civ3, and then applies those settings to a game with classic ruleset, in addition to the settings that user has changed themselves, a lot of civ2civ3-set settings get set.