Crate Bug

In some of the Custom Levels you can encounter the movable crate bug. It allows you to get past a movable crate and into the area behind. This might only work if there is space behind the crate.

Stand in front of the crate, in the middle.

Now turn sideways so that your back is towards the side passage behind the crate. (See the picture, the little gif shows you where the other passage is.

If you press Action now, Lara will sidestep through the crate and will end up in the other passage.

Of course you can repeat this as often as you like and can reach all sides of the crate, if there is enough space to stand.