Float glass fires about 30-40 degrees C higher than Bullseye - I do a full fuse at about 835 in my kiln.
The cloudiness is most probably tin bloom, or it could be de-vitrification if you have been in the devit zone for a long time (depends on what firing schedule you used, why don't you tell us what that was?)
You also need to be scrupulous about cleaning float glass, it doesn't let you get away with anything!
You'll find fusing schedules in this section of the forum:
http://www.frit-happens.co.uk/forum/index.php?board=12.0As well as information about float glass within this section of the board that you have posted in.
HTH