This Apple script will resize any program window to an exact size and the window is then moved to the center of your screen. Specify the program name, height and width below and run the script.
Written by Amit Agarwal on December 10, 2013
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set theApp to "Google Chrome" set appHeight to 600 set appWidth to 1000
tell application "Finder" set screenResolution to bounds of window of desktop end tell
set screenWidth to item 3 of screenResolution set screenHeight to item 4 of screenResolution
tell application theApp activate reopen set yAxis to (screenHeight - appHeight) / 2 as integer set xAxis to (screenWidth - appWidth) / 2 as integer set the bounds of the first window to {xAxis, yAxis, appWidth + xAxis, appHeight + yAxis} end tell