YOP !! I had a general issue regarding snapping blocks together that WERE already attached at the position before. CASE : I need to repair a tech after a combat, snapp a Cruise at its previous position in a row : I can't. I can remove and re-snap the n°1 at the right but not the N°2 Then on the top, I need to replace a GSO missile. I can't. It was there before. For test purpose, I remove the solar gen just at the back. I try to re-snapp it. I can't. But I can place it just one step at the left. I checked if there was some trapped blocks stuck within my tech, nothing. I tryed both in Build mode, on the ground and anchored. Its like suddenly the anti-intersect mechanism just became crazy Then I did a save, and restarted the game, no more issue. I can now resnap everything in place. EDIT I just had the same issue when building a platform. Not immediately, but after after adding around 150 blocks. Suddenly one block refuses to snap, it was blinking transparent red and green like if it was hesitating between two states. I was able to snap it by chance, but any other blocks failed. From this point, impossible to continue any build. Each time I remove a block i'm unable to snap it again in the same position. ... until I restart the game.