Toma,
I just galloped through your code, but I'm not sure what you need exactly.....
OK, you do have 2 fields and a button.
I need to refresh automatically the content of the users_list field depends of the k_org value.
Does this mean, if the user clicks on the radiobutton, then the above mentioned code (sub click...) should be executed?
If so, maybe you could use the postrecalc-event!? Or the exiting-event of the radiobutton-field (not that perfect).