I am just noticing that an empty integer number field cannot be tested for being empty: If I use the length( function, it returns 1, and the value shown in the Formula Workshop is 0.
To test an integer number field for empty, use the sizeof( function. This is exactly the same as Panorama 6, in fact, that is the reason the sizeof( function exists. In Panorama 6 if you used the length( function on a numeric field you would get a type mismatch error – Panorama X is a lot more forgiving so it converts the number to text and then returns the length.
I just saw that this is the same behavior as in Panorama 6.
Thanks for reminding me of the sizeof( function!