I also have the same problem with smoke effects in CUP.
Things are fine with the vanilla game.
But with CUP, smoke effects turn 60fps into a slide show (5-10fps). Most noticeable when looking at burning plumes of smoke on the ground (fps recovers immediately when they are not in view).
I found this could be mitigated slightly by setting "DynamicalLights=1", rather than 2, in conf.ini, but it's still a problem whenever there is more than one smoke column.
No doubt related to our PC's ability to handle the graphics. Mine isn't top end, but plays the rest of the game (and vanilla), fine so it feels to me like the smoke effects in CUP could do with some optimising if possible.
i5-2500K @3.3GHz, 8GB, HD5850 (1GB), Win7 64.
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