Hello HomerJ,
The recommended way is to mark the entity as required in the project customization section accessed through the tools menu. The following thread addresses that issue: http://eyeontesting.com/questions/3314/making-fields-requirement-fields-required-qcalm-11.html

Now if the fields are greyed out, and the customized workflow isn't working as expected, then there is another thing to look into. I have experienced in the past where the project is attached to a template and if that is the case the customizations will need to be applied to the template and then pushed out to the desired projects or the projects will need to be disconnected from the template. As long as the template is attached to the project you will need to apply all changes to the template first and then have them pushed out to the project to apply.

Having said that the ways to find out if the project is associated with a template will be to look at the project properties within SIteAdmin and you can see the project being attached to a template or within the customization section for the project within the customized work flow, at the top of the scripts listings will be a section that refers to Template scripts. This section only appears on projects that are associated with projects.

I hope this helps,
Dan