Unwelding a blueprint does really really weird things

[ocnoglittle 760]

Using YadNi's palette (thank you @YadNiMonde!), I was trying to see which blocks can blueprint. I put it on a legacy exploration map, then captured and placed the blueprint. I then was trying to click on the blueprint blocks in editor, and realized most of them were welded together. But when I try to unweld it, it does crazy things. It seems to add the items that were in the blueprint that hadn't been welded and deletes all the blocks from the weld:

Before unwelding (attached as a zipped composition):

After unwelding:

Original palette, and blueprint above it:

 

 

FROM BLUEPRINT.zip