
If you're dead-set on 2-way symmetry, the easy solution is to just click-copy the inner booster (from the decoupler) and apply that. This somewhat limits the usefulness, or at least can require you to jump through hoops to get the root part to be where it needs to be for a particular application. Every subassembly has a particular "root" part, and it won't attach to anything except by that root part. If you loaded it from a subassembly, that's likely your problem right there. How did you "create" that booster that you're trying to hook on? Did you save it as a subassembly? Or did you click-copy it from one of the existing boosters? I then tried side to side like you see-and again it absolutely won't attach to the decoupler, although I did manage to get it attached once slightly inside the other booster. Could it be better? Sure, but the cure could also be worse than the problem, so take a few minutes to understand the situation and this too shall pass.I then built the 2x design you see and attached another pair of decouplers front and back-and absolutely couldn't get the booster hooked to them.

I agree but also understand that once you get the hang of it, it's not an issue any more. Now seeing this, please don't come back and tell me it's not what it should be.


It is essential to understand that the mounting point of the tank is EXACTLY where the mouse cursor is at the moment you left-click to place it. Not justifying the software or blaming it, but this is a common issue with noob's (including myself a ways back.)
