Arima I realise that when it comes to rendering, placed in a petri dish, C2 performs well, it's when you ask these objects to do something other than look pretty that things seem to go a bit pear shaped...
For simple games C2 performs great, but do fear for anyone developing anything remotely complex, when it reaches the end user with far lower spec than the Dev developed and intended it to be played on...
The chrome 32 update really has thrown the spanner in the works, and yes one of the cards was blacklisted, overcome with chrome//flags
As far as I am aware windows 7 supports and uses hardware rendering for 2.5D displays (desktop windows), and XP does not, so if what you say is true, I'd have expected increased performance on Windows 7, but, I am not 100% up on all the Tech regarding video cards, so bow to Your better knowledge on that...
To be honest My game is still performing as good as, if not better than most similar games, I have seen or played on the forums, it's just about acceptable, but I continue...
Looks like I'm as guilty as everyone else, when it comes to dropping My expectations as I add more game play elements...