In the pattern object, I had part of the object that wasn't supposed to be seen a bit too long. It was part of a fence that was suposed to be in the end post of the start object, and a fraction of it was protruding past the post.. Once I shortened it, the pieces came together.
On anothor one, I had made a privacy tarpolin over a chainnlink fence. The Alpha dds of the tarpolin was on a 3DSimEd primitive that was fractionally larger than the complete fence, even though the artwork was the correct size to cover the chainlink. When I shortened the primitive to only cover the chainlink, the fence pieces came together.
I've done quite a bit of basic modding for GTL & GTR2, so I do like the challenge of fixing my hiccups.