Im getting about 270k per hour with 260% GF now i miss zero cellars before it was about 200K. Thats with gems and tombs and all looting options turned on and selling all magics and stashing all rares every 7 trips. Yea it does seem that finding the cellar is different for everyone for example if i run on my laptop instead of my main pc i see a different distribution of success rates across the points and thats with the same account and barbarian so im guessing hardware dependant somehow, impossible to pin down really so i suggest everyone do what i did and have it screenshot every failure and note down the position of missed cellars.
I have added an option to my latest script todo this it will save images to a subfolder "shots"
DO NOT LEAVE IT ON TOO LONG, IT WILL USE ALOT OF DISK SPACE!! set $TakeMissShots to true and let it run then check your shots folder and see if any show an open cellar if they do note the co-ords in your fav image program and add them to the list in the script (dont forget to modify the array length [4] to how many points you want)
its incorporated here:
http://pastebin.com/PtE6XJ4W