My take on the state of affairs regarding your less-than-perfect rifle is this. What is done, is done. Why beat up the guy you chose to finish the rifle after you did 40% of the work, as some here so strenuously suggest? Will exacting a pound of flesh from him, make him discontinue his hobby or make you happier tomorrow? That would be a no, for me.
Yes, he should not have drilled out the ramrod hole. Now you simply need to have the crack filled with superglue as some here can expertly do or can oversee. Don't just wing it. The rifle is not seriously compromised, strength-wise, by this crack, in my opinion.
The triggers should be studied and likely removed for a repair, and I would leave this to someone knowledgeable in these triggers and this kit. Jim Kibler would be my first phone call here.
The lock screw could likely be straightened by someone, as I know I would try this for myself. Again, the repair requires experience. Or just buy a new screw, and no dry-firing without a flint properly fitted, please.
I don't sense despair on your part, and you need not either. You are on your way to a very nice rifle and you can learn from this experience, the advise and very many lessons on this site and give another kit a go sometime. Thanks for sharing.