Take it slowly, it's only a car. If it was working when you took it off, then you have not replaced the item removed correctly or a seal has not been achieved that's why the pump keep running .
go to my site and study the page then start again, the boot lock problem will be lack of servicing , Serviced by a gargae MB? well that will be the answer the chances of it having seen more than the lubricant spray can will explain why all the conponents are dry and have locked up.
Door locks, boot lock, bonnet securing devise, fuel filler lock, all want regular lubrication to keep them working well silicone spray twice a year does the job for me.
Oh and if you like a copy of my CD please order in the next 6 days It must go up in price towards the end of the week ..
http://www.aclassinfo.co.uk./mypage.41.htm
Please come back with 'feed back' and tell us how you get on, I can't speak for others but I like to hear the good news as well as the bad.
lofty