need help with getting nickelmenu scripts to work

I am trying to make a script that moves the screenshots to /mnt/onboard/.screenshots/

menu_item :main    :Screenshot move     :cmd_spawn         :mv /mnt/onboard/screen_*.png /mnt/onboard/.screenshots/    

works but

menu_item :main    :Screenshot move     :cmd_spawn         :/mnt/onboard/.adds/scripts/screenshots.sh

with the .adds/scripts/screenshots.sh being

mv /mnt/onboard/screen_*.png /mnt/onboard/.screenshots/

doesn't work.

which if I just wanted it to be that wouldn't be that big of an issue but my end goal is something like

for file in /mnt/onboard/screen_*.png
do
mv /mnt/onboard/.screenshots/$(basename $file)_$(date +"%d%m%y%H:%M:%S").png
done

to hopefully timestamp them and not have override issues until I am able to move them out of the folder

anyone able to tell me what I am doing wrong?