"Open in Low Resolution" - what does it actually do?
Say you have you're screen set to standard (using 15" as an example here), then "it looks like" 1440x900 but it is really 2880 x 1800. Making this example easy, say the app runs in fullscreen, then it would usually load with 2880x1800. If you check the "Open in Low Resolution" it will load in 1440x900, thus being less sharp but in some cases better performing or preventing bugs if the app is not optimized.