Hey

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just a thought came to mind as I was reading this, what about giving your dog a max time of 2-3 minutes, if he doesn't do his business then take him back inside. wait 10-15 even 20 mins, then try again, give him 2-3 mins and if nothing, back inside, eventually he'll have to go enough that he'll go within the 2-3 minutes and then give him lots of praise and special treats. This might take a while though and someone else might have something more effective but just thought I'd throw it out there ;o)
Also, Corky's suggestions are great, in terms of getting him to be less fearful of noises. you have to desensitize him to normal every day sounds. This can be a long process as these types of fears can be some of the hardest and most time consuming to reconcile. I might even enlist the help of a professional trainer in your area, someone who can see the dog first hand and get a good idea of a training regime that could work best.
A suggestion I have though would be for example the cupboard door, put your dog on a leash or block off the exits so that he can't flee the situation, when dogs are scared it triggers a flight response and they just want to run away, if you block them from being able to flee you, in a sense, force them to deal with the situation through other means. (I.e. working it out in his head that the cupboard door opening and closing is not going to kill him!)
Start by just opening the door and closing it without making a noise, do that a few times then close it making a very slight click a few times, every time you open and close the door and your dog does not freak out, give him a treat and praise. Eventually close the door harder and work up to being able to slam the door and your dog doesn't flinch. This could take a few days and I recommend working on it in short bursts a number of times throughout the day.
If you do close the door and at any point your dog tries to run away, go back a step, maybe all the way to just opening it and closing it with no sound, then treat when he does not try to run. then end the session and start again in a few hours. Always try to end each session on a good note, with some type of success as opposed to ending it right after he gets to the point of actually being scared.
Once he gets good a cupboards, switch to any number of other things he may be scared of and repeat the same process again.
Good Luck!