... so, here's a really hard one.

Make no mistake: if there are no loopholes, then this might be the most complicated level I've ever produced. I know that's a pretty big "if" considering the nature of the layout (especially with gate reusing) but I couldn't find any puzzle-breaking loopholes. I would've done more testing, but I wanted to release it in time for the New Year.

I even wanted to decorate the level with a custom texture (and would've chosen "wintersnow" had I done so) but in the end I couldn't do this: there are 1-step and 2-step bridges in this level and the distinction is absolutely crucial. Pay close attention.
***
You know my style of "pack A LOT of puzzling and movement into 14x14", right? Now imagine a 28x28 level designed the same way. There are many tricks (including two that I've never combined before) and multiple instances of going back and forth in a highly specific order to do something that isn't obvious.
Note that the solution is very time-consuming. I did give you the comfort of all 15 minutes on the timer and even put three alarm clocks inside the level, but there's a very good reason I did that.

Granted, I was quite slow in parts, just to make absolutely sure I didn't mess up, but even knowing the solution, it took me over 10 minutes to do it. So you may want to figure out the puzzle in untimed mode. It's that long, despite only being 28x28 in size.
EDIT: Version B is up. If you solved the level the intended way (or are still stuck) the difference is barely noticeable.
EDIT 2: Version C is up. If you solved the level the intended way (or are still stuck) the differences, though noticeable, will not seem significant, except for one break tile that forces you to use a certain box in a smarter way. However, some serious shortcuts are closed.
Version B is removed. The original is still there for comparison.