I mean, that's fair--I didn't realize this was a jam game. As for my guesses to the questions I asked: I don't really have any, that's why I picked those specific questions; I don't have evidence from within the narrative itself to base any guesses on, anything I offered would necessarily just be based on my familiarity with sci-fi tropes from other media.
To get more in-depth: the player is never told what the device does, we know it interfaces with ???????? and the lack of cell-localization could be catastrophic because ???????? and creates a stasis field that affects everyone, even itself which may be how it has frozen everyone in place and stops itself from ???????? so you need to shut down power to the entire facility; we also know that it trapped David in the network. That's actually a pretty detailed description of what it does, I should have asked what its purpose is. Why would this outcome ever be desirable? Or what was it supposed to do that it failed to? Making a few assumptions that are not entirely based in what the player is provided, we can fill in the blanks above: if we assume it provides an interface between the brain and computers, we can also assume the "cell" in cell-localization refers to brain cells. That might also explain David's motivation: digital immortality as a cure for a fatal illness. But it still wouldn't explain why it causes everyone else to be frozen in place, why that would be a side effect or even desirable outcome of uploading your consciousness to a computer, nor why he is drawing the player character down into a pit from which there is seemingly no escape; if he's to be believed, why would he trap us down there with him? If he's not trustworthy, why should anything he says be taken into consideration when piecing together the story?