When enabling Large Key Figure (LKF) in BPC 11.1, the Model options note that doing so could result in some script logic incompatibility. See item #2 in the screenshot below:
Does anyone have a comprehensive list of which Script Logic statements/syntaxes are supported by the Normal key figure length, but not supported by LKF?
I also found a couple other Notes alluding to specific script logic regressions caused by LKF:
However, I have yet to find a complete list of script logic regressions caused by enabling LKF.
Unfortunately, there is no official list. You have to test your logic yourself in a test model.