Answer: scroll below - very small fonts so zoom (control-+ or control-mousewheel)
Answer: I'd say well above 3500! both players are GMs who are experienced in computer-correspondence chess, and this was computers+databases+tablebases allowed, average 6 days per move!
So of couse I cannot point out mistakes if any; if your engine finds an 'improvement' over a move, run it for a few more days: it will probably not be an improvement!
Puzzle: how would you rate the players in the following game? Names have been omitted with permission. Answer in smallest fonts in next post.