there is a bug in the knime reporting related to using the Highlighting feature.
Take a numerical column with some missing values in it, and then in knime reporting set up a highlighting feature such as to make a cell go red based on the conditional rule of; if columnA is <x where x can really be any value.
you will find that the cell still goes red even for the missing values. Surely this is a bug, it seems as though missing values are being treated as a negative infinity value.
If the conditional rule is set as a > instead of a <, then the cell does not go red, further suggesting that missing values are treated as negative infinity values.