2001 Mercury Sable Cruise Control Problem

[ligenzch]

a little history: i have a 2001 mercury sable that got a rebuilt transmission in april of 2011 by aamco. in june of 2012 i took my car to a local mechanic because i had to have my water pump replaced because i was leaking coolant. three months later the car had to go back to the mechanic for ANOTHER water pump. within 2 hours of getting my car back the transaxle light illuminated and the car began to hum and idle at 2 RPMs even while in park. i took it to the mechanic who just replaced my water pump and they said it was an internal transmission problem. with that being said i called aamco (since they had worked on my transmission) and they wound up replacing 2 engine mounts and the idle sensor. not even a week later when i went to park my car it started fuming and all the coolant had emptied out so back i went to the local mechanic, who replaced my water pump, and they went ahead and replaced the coolant tank and some other lines and hoses. when i went to pick the car up they asked who had worked on my transmission because they noticed that the cruise control lines were now broken/disconnected. my question is if the cruise control line couldve gotten broken from the engine mounts going bad and if so shouldnt aamco have brought this to my attention and/or fixed it? if the engine mounts couldnt have been the problem then what possibly couldve have caused this? i only use my control when on the highway which is not that frequent but from what i gathered from the mechanic if i would have tried to use it in the current condition the car wouldve taken off on me which sounds pretty life-threatening. I am not much of an auto expert which is why i would like some clarification as to what may have happened here. thanks!