a required checkbox for a disclamer for content types (a widespread necessity I think)

I place before that I'm not a champion with Drupal and less with cck
and so may be it's my guilt.

I was in need to add in a content type (used to post photos) a disclamer to accept responsibility concerning the inputing content.
I did not succeeded to create the -required checkbox-.

No success: no asterisk on my check box with my disclamer.

My way:
I chose integer field type and as widget -Single on/off Checkbox-
I click on -save- and then I leaved blank all the field except

Help text (my disclamer)
required (checked)
Number of values (1)

If my way it's correct the problem is serious.
If I mistake something I ask if someone would be so kind to post or link the way to create a little disclamer dedicated to the risk content (photos, music.. but I think every kind of contents could need it).
I search by google but there is not a clear little guide or post about it.
I think the disclamer on content type may be a widespread necessity.

Now about disclamer I solved provvisoriamente temporarily (I post it cause it can help someone like me) setting that field (going in /content/node-type/node_name/display) with all set on -hidden- and checking all the -Exclude- checkbox (obviously limitedly to that field)
That let the disclamer displays with the red asterisk. And the disclamer may starts with "Clicking Save ..." . Not so bad IMHO.

On my drupal installation (6.9) I installed Checkbox Validate module

thanks by now for any help
fab