So I was trying to reproduce this but I could not figure it out. Can you give me a few more details? What key are you using to rotate the blueprint? The 'R' key should be separate from the "oblong rotation key".
A little clarification. The error occurs in vanilla mechanics, because the mod remembers the last object that was changed, and then allows you to change it without hovering over it with the cursor. And when the blueprint rotates, the game considers that the last modified combinator should also be rotated.
