Custom list button to send emails to multiple emails

[SRiber]

Hi,

I have now spent two days on this with nothing much to show for it. What I'm trying to do (besides avoiding visualforce which I have never used) is to get a custom button on a custom object related list under cases. Long story short, I have replaced CaseContactRole with a custom object as it did not do the things we needed and it this also allowed us to do triggers directly on the new object which we needed.

But now I cannot get it to compile a email template with all the email addresses of the contact roles (which are now called candidates__c).

I have the button, and I have gotten it to assign the case to the template so that is compiling. But I cannot for the life of me connect it to information related to the custom object, and therefore cannot get the email addresses. This is what I have used so far:

location.replace('/email/author/emailauthor.jsp?retURL=/&p3_lkid={!Case.Id}&rtype=003&p2_lkid=&p24=&p4=&p5=&template_id=00XA0000001Whhn');

No matter what specific field or which p I assign it to, no {!Candidate__c.XXX} is bringing up anything. The url just looks like the above, and I have therefore removed them altogether hoping that someone in this community can help me. 

Thanks a million!

Soren