Nice article, very interesting if you're interested in game engines and stuff. It also explains the performance improvements well. I was wondering, are the timing fixes also applied on a linux client and on the server?
There's a small mistake in your code:
else if (OldTime > 0xF0000000 && NewTime < 0x10000000)
OltTime = NewTime;
Oldtime is spelled wrong, and as far as I understand it it wouldn't change anything for OldTime won't be used after that line again.