Graphical build lags for me regardless of tiles are on or off.
It generally seems a bit unstable too.
In terms of computer performance, you do need a fairly average computer to get a playable version of cataclysm (with the occasional slowdown).
I have 1 older machine dedicated to cataclysm development, it can run the game but there is a definite 50-100 ms delay between movements and such.
That machine has a rather old dual core, however it is running lubuntu which really makes up for the low performance.
My two other computers have i7’ in them, the only difference being a slightly better graphics card in one.
And windows 8 on the other.
Both of these run cataclysm without a hitch, waiting a whole day typically takes around 10 seconds, depends what’s going on around me 
On my linux machine it takes 2-8 minutes. Depending on environmental factors.