I wouldn't worry about it - my car idles rough (noticeably shudders every few secs) when cold, but sorts itself out when warm (as oil temp pases 1/4 mark).
Remap has made cold startup slightly rougher, but Ii don't mind because once it's warm it flys!
One tip my mechanic gave me - every month, take a cruise in low gear with revs between 4-5k rpm to get the cylinder temp up (engine can take it). You'll notice oil temp pass 1/2 mark, then I usually back off. Aim is to burn off carbon deposits in the cyclinder so allow your engine to run more smoothly. See if that makes a difference...