Hi Sai,
I was using check box for logical operation like "Is Initital or IS NOT INITIAL", If MKPF-WEVER is not this much required then create globle variable like GW_IND type char1. and use GW_IND for check box.
Just remove MKPF-WEVER from name and give your GW_IND.
for just accuracy delete check box Element from screen and create new check box with GW_IND.
Regards
Amit