As mentioned, we were told that S&W bought and installed some new CNC equipment for that plant, and did some additional upgrades, when they were moving the 3rd gen production capability there (meaning they're still making them upon order for established/existing LE agency customers). They moved the 3rd gen production out of Springfield to make room for the TC manufacturing equipment being moved there, and some increased production capability in the M&P model lines.
The SW1911 production has already been occurring at Houlton for the last 3-4 years, if I recall correctly.
Their .22's are made there, including the M41's.
As far as the production of the licensed PPK & PPK/S pistols? From what I've heard I'd suspect that's more of a couple of design change/revision issues that have required adjustment than a production capability issue.
As long as the production cell assemblers have been taught to fit the extractors & sear release levers correctly, and to check for any tolerance issues in the area of the drawbar head's radius & trigger pin contact (causing Skips-DA), I can't see why there would be any issues in moving the production to the other plant.
I wouldn't be at all surprised if it turned out that occasional 3rd gen guns to come out of Houlton were even better. New equipment, increasingly better tolerances and manufacturing of new parts, etc.