Main Dealer Service Spark plugs leads off !!

[TVRWhoa]

Large rant warning ! About 5/6 weeks ago picked up Chim from a Main Dealer in the N.West after major 36k service. Driving home it promptly died completely blocking Runcorn bridge, after an hour recovery truck tows me off. (What an advert for TVR).Car left in a nearby industrial estate. Phone dealer, rant and rage how could car could break down so quickly. Told nothing they could do, could I get car to them - episode of nearly fatal hypertension at this point, so phoned the AA. AA man finds lead to coil was not in properly and had fell off !! Cue more ranting and raging at dealer next day and given £100 compensation - rage having subsided,accepted apology and thought nothing more of this sorry tale. Last couple of weeks noticed car seemed noisy and down on power, looked at leads on distributor cap and all seemed o.k. Checked plug leads and would you believe it, spark plugs lead nearest to the windscreen on both sides of engine completely off and dangling down the side, so for the last 5/6 weeks have been running on 6 cylinders. Sorry if this is a bit long but I need to get this off my chest; So to the point, could pistonheaders give me their tuppence worth on this -
What could this have done to the car, is there anything I should check ? any lasting damage ?things to look out for? Could cats be damaged ? Car appears to be running o.k. now leads are back on.letter of complaint to dealer and TVR to follow me thinks.