Okay, source of the problem. The db table that holds the style information had a "tiny integer" column for the Recordid. What looks silly on our side is that the code is removing and inserting on each save, rather than an update. You must been saving so many times in there (probably using debug trace) that did what nobody has every done before: you maxed out the size of the tinyint column.
It's bad code on our side. What we did was change it to be an "integer" size, so its much bigger.
Problem, though is that we lost any custom style setting. Would you like us to restore a backup and copy and paste the style back in for you from your old settings?
Paul