Field help (AEXPCONCH) 

When this condition is met, the cell in the grid will take the color defined by the conditional style.

This condition, expressed with the usual functions and operators of the language, can only assign to the line the value of the current field specified with zc in the formula, constants and global variables that will need to be assessed in the context. For example: zc<0 or zc>GPRIXLIM and GUSER="ADMIN".

Regarding those conditions that implement a date, the constants need to be always expressed in the form [DD/MM/YYYY], irrespective of the regional options set by the user.