OK. I used the new converter on my 1773-1819 Britain game. I'll comment on each of the changes listed.
"Gave China + many other territories extra population. China ~100 mil."
This doesn't seem to have happened. China only had 186 million people. What were the other territories? Extra population should be based on multiplying EU2 population, not just adding lumps of extra people.
"Generally cut population in half, except for some areas that get more (China, Korea, Indochina etc.) and some that get less.
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"
Presumably only for early games. I'll convert one of these later to test this. Certainly this change wasn't in affect in this conversion.
"Yankee and dixie population in the USA are doubled."
What about British population?
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Broadly, not enough people in the Americas as a whole, for late games at least.
"Toned down prestige modifier to 0.05."
Prestige seemed fine.
"It's now a little bit harder to get civilized in later scenarios."
This is movement in the right direction- a lot more uncivilised countries in this conversion than before. However you could stand to go further. There were still nine uncivs that were civilised this time around- including China, which had been a mess. Civilised China can be game-breaking.
"Added Literacy conversion."
For Latin tech group countries this worked just fine- a lot of the literacy values looked like they could have been from the GC. Russia, Ottoman and the uncivs had too high literacy, however. What was the formula used? Perhaps tech group should play a major role.
Moving in the right direction here. Keep it up- will do some more tests later.