I'm sure I'm not the first to mention this.
I understand (basically) how remix works - so I can see some probs with allowing remix (or indeed rebuild) working across the interface between locked and unlocked segs. But surely it would be a great advantage to be able to do so?
Being unable simply restricts design by players - maybe I'm missing something. But this does not seem productive for many puzzles.
For example - I suggest the results for ILR7 are nowhere near where they might have been.
Not being able to so this makes such puzzles less controllable - but perhaps this is the intention - IDK
Just my 2 pennies worth.