The kiln shelves look like the glazes are spitting during the firing, which could be a sign of firing too fast for the glaze you are using. Our studio had a really great blue that spit -- and would contaminate any pot on the shelf next to it. Same for the pot that rejects glaze in parts -- firing too fast (and maybe glaze too thick) to allow a good melt. Glazes bubble on the pot surface when you are at top temperature. Try a slower glaze firing, especially the last few hundred degrees before you reach top temperature.
Test tiles are great, but they don't often show how the glaze acts on a full surface, curved surface, etc.
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