Weird Failed Intersection Issue

Hi all.

Could someone take a quick look at my definition? I'm getting a "Failed Intersection" for some reason and I don't know why. This isn't complicated. I'm basically pulling the intersection between 2 sets of spheres and a cylinder. I've had various problems with intersections dropping out or only going part way across in this definition and I don't know why. I've been able to reduce it somewhat by moving the spheres to the opposite side from the seam of the cylinder, but it's still happening. What's dropping out changes when you adjust the size of the cylinder or number of spheres. You can see in this one that there is a full pipe missing 6 or so rows in, though sometimes it only drops out of the top or bottom set.

Also, while you're looking, I'd like to know how to close a couple surfaces so they register as breps and can be booleaned. The 2 pipes at the top & bottom of the cylinder, as well as the fully revolved surface that isn't turned on in this photo. I can probably figure this out after baking, but I like to try to get things tidy in GH if I can.

Thanks for looking!