Showing images instead of values (Modules)

Hi there,

I am new to zoho and I am exploring .. noisy. And it seems that I did chose the right CRM....

I like to use an image instead of a value which should be shown when viewing a customer.

The idea:
With a formula field I am checking if all required customer data are filled.
If "yes" then show a "green_dot.gif" if "no" show a "red_dot.gif". How can I solve this?

Thanks for your help in advance...

Patrick