First and foremost, my best wishes for a satisfactory outcome with the factory. Second, maintain sanity. It's only a "thing" manufactured by man.
Third, try VERY HARD, not to be upset and scream at the person to whom you are speaking. It will not help and your blood pressure will rise.
Now reality: make a list of every flaw you see at this point. Make sure when you communicate with the dealer or the factory that you document the date; time; to whom you communicated; the issue discussed and next step course of action. If follow up is committed, make notes and place it on your calendar to ensure it happens. Whenever practical, ask any person you communicate with to e mail you a confirmation of the commitment. These could be potentially critical should you need a lawyer down the road.
NEVER ASSUME anything! PERIOD. The factory will do the minimum it can to make you satisfied.
At this point, you did not get what you paid for and you want that corrected (or replaced) do not assume that a different unit will be any better, UNLESS you buy one in stock from a dealer lot and do a thorough PDI and take it nearby and camp in it for 2-3 nights.
Most of us who purchased Keystone products are "overall" satisfied and would buy another one. That does not excuse poor craftsmanship. BUT, most things can be fixed or replaced.
If you strongly feel the unit needs to be replaced, state your case in a letter and send it, certified, return receipt requested, to BOTH the dealer and factory. Give them a time frame in which you expect to hear from them; ie, 7 to 10 business days from receipt of your letter.
Be professional and courteous. This is a start. You can always be more stern just before you seek legal assistance. IF you hire a lawyer, they likely will take a similar approach at the beginning of the process. They will CHARGE YOU for every phone call to anyone, every letter written, every follow up, etc. You may be stuck paying these fees out of pocket. The result may not be any different than you could achieve on your own.
LAST: be patient. Have a cup of coffee. It will get better.