I’m still relatively new to this engine…
Does it matter where you start a level? Is 0,0,0 okay. Would it be better at say, 500,500,500?
If I move an asset into negative space, will this cause a problem with anything like Physics, Blueprint functions etc?
(reason why I’m asking is the Cryengine had a huge bug that cutoff all physics in negative space, I don’t want to go through something like that again 
)
I’ve not run into anything of the sort, and everything I’ve built thus far has been roughly centered around the origin.
Worth noting though, if you have to offset, (500,500,500) won’t be enough. Unreal 4 is in centimeters. 
Distance from 0,0,0(and by that i mean as you get near and beyond the grid you see in top view) matters for physics but i’ve never heard or encountered any issues with negative coordinates.
Could you further explain what happens to the physics as you get near and beyond the grid in the top view?
Physics calculations wont be as precise and you’ll also start to see lighting glitches. For instance you wouldnt want to go beyond the world limits if you are making a game with vehicles. You can use World Composition if you want larger environments though, since it lets you reset world origin.
Thanks for the info, good to know
So, what would you recommend when starting a new map? Stay a few hundred meters away from the origin?
How can I tell I’m going beyond the world limits?
Just keep the whole playable area inside the grid and you’ll be fine. You can see the grid in top view.
Got it, thanks.
Precision goes down as the coordinate numbers get bigger, since it takes longer to process the larger numbers, so it’s best to keep everything as close to the origin as possible.
It’s not processing speed it’s that the numbers themselves are literally less precise (roughly) the further you get from 0.
So, Integers are actually lies? 
Integers are reliable, it’s those shifty Floats and Doubles you have to keep an eye on.