Unequivocally do not recommend anyone watch this, it brings nothing new to the table, and actually manages to tarnish the *Cube* name.

Totally agree with @movieswatcher, at about the 1h10 mark, the movie just completely goes off the rails and gets annoyingly bad.

Even so, from the get-go it's just a messy story:
The characters are all weirdly invested in each other after barely speaking to each other, let alone getting to know one another. Speaking of, there doesn't even seem to be that much time passing, like were they in there just a few hours? Then there's that utterly unnecessary [spoiler] gate that comes up in between the group, separating [/spoiler] them because... who the heck knows? They could have easily used the doors closing as a similar plot device, but no.

Then the subplot of the dude who keeps freezing up because of some boring [spoiler] childhood trauma [/spoiler] (that we keept being shown repeatedly). Eventually it even gets [spoiler] projected onto one of the walls [/spoiler] of the cube... what, why ? Let him tell the story, then react, and we can guess it's from the only info we know about him (said story).


Finally, what was with the super generic [spoiler] generational age gape [/spoiler] hatred which @movieswatcher mentioned as well ?
Additionally, that completely useless female character who never speaks and is way to obvious in her acting, revealing within minutes that she's [spoiler] in fact a robot [/spoiler]. Then the rooms reacting to the [spoiler] crazy guy's mood [/spoiler] which once again: served no purpose, doesn't make things interesting, and it doesn't advance the plot... it's there, and adds nothing of value.

Kinda like this whole movie: adds nothing of value. Skip, and go re-watch the original.