Hmm. If you bought it yesterday it should be the latest version already. That's weird that it starts okay and then gets slow. Can you tell me your system specs?
I don't know too much of what goes on behind the screen, but here goes:
xin 10 home, 64bit
intel core i5-3230m, 2.6ghz
8gb ram
nvidia Geforcre GT750M, 6087 mb
1920x1080 60hz
its a lenovo laptop
Yeah it is weird, it seems like it happens pretty sudden the shift to slow...
thanks for the answer and the promising game:)