Gee whiz, I got to the forum earlier today and signed in to update this, and then just didn't do it. Thanks for the prod Billy.
I emailed the photos to Amanda who showed them to Kermit who called me. He said that the "sag" I'm seeing is... not by design exactly, but sort of a side-effect of how the corner is put together, and not something I should worry about.
As far as the crack, he identified it as a substandard caulk job and promptly sent us the caulk to use for it, as several people here suggested. I managed that a couple of days ago. No problem.
I'm really grateful for Kermit's response and handling of the issue.
This is where the story turns a bit sour. I would like to get back up there and check on it, but both of the linchpins that hold the ladder on at the bottom have now failed, so it's not safe to climb. I've contacted Amanda and hopefully they'll get me replacements to us soon.
What's frustrating for me is that we have all of our stuff in storage and we're supposed to be on the road right now. Instead, we've been taken in by sympathetic relatives for the past few weeks dealing with all the various problems we've encountered.
To be fair, a whole lot of the problems we're having have nothing at all to do with Phoenix Cruiser. The spectacular hassle involved with getting our tow vehicle towable has me absolutely spitting nails, and it looks like there's at least another 1-2 weeks of delays. Suffice to say that if/when we ever do get on the road, I am sorely tempted to make our way to Washington State and burn down the Roadmaster factory.
Once I do, then we'll be back to (even more) PC issues. I've been pacing myself asking about problems here so I don't sound too needy. But the truth? There is way too much rust visible for a brand new unit we've had for two months... there are signs of rust all the way around the RV door and around the rear (fiberglass) trunk compartment. (The reason for the linchpin failures was also corrosion.) There's a growing bubble under the paint on one of the cab doors. Not one of the fiberglass compartments closes smoothly, and they're getting worse; at first they were merely difficult but now I have to put my entire body weight against the compartment doors to turn the key. I've already literally twisted one of the outside keys in half trying to lock the compartments. I've fixed three plumbing leaks so far and it's still not clear I've gotten them all. (I think there may still be one related to the black tank -- yuck.)
This is all stuff that's got to be dealt with, and there's something new every time I turn around.
Here I think is one of the issues with buying from Phoenix Cruiser... nobody wants to deal with us. Even places like Camping World are telling us that maybe they can squeeze us in (to install stuff we bought from them) in 3-4 weeks. If we had bought from a dealer with a service department, at least we'd have somebody to lean on / yell at.
Sooner or later all of this stuff will get ironed out. But, our "vacation" schedule is limited, and we're watching it slip through our fingers week after week. And I'm not really on vacation; I work remotely, so the plan was to do at least some work while we were on the road. But not right now; working on the RV is literally a full time job, and my real job is suffering big time.
I didn't buy an RV to park it across the street and stay in my relatives' guest room. And I'm just not sure I have the stamina to deal with this constant stream of issues.
(Important note: I don't think any of the problems we're having are anything that wouldn't have been just as likely with any other manufacturer. I understood that all RVs have quality issues before I bought. I'm just really frustrated right now, and running out of rope on the whole thing.)