So I'm starting off with a 2048x2048 atlas (I don't want to use anything larger) with two different window sprites:

Notice there is still plenty of room on the right side (around 150 pixels of width).
Then I try to add this 32x1536 gradient strip to tile as a background, and it acts like there is not enough room for it:

Anyone know why it can't fit all three?
Side Note: Is 32 pixels not wide enough for that gradient strip? I get Unity warnings about it occasionally, but it seems to work once I tweak the location on the atlas a little bit.