exim

Hey there,
Tried to get my systems administrator to install og2list today.
He replied:
" Are you sure you want us to make all those mail router configuration changes to your exim config. I do not see cpanel supporting this software and so mails on other domains may get messed up by this. "

So I ask you: "Will og2list work with a dedicated host running cpanel/whm?"
When I tried to add the settings to my exim.conf file on my own all other mail stopped.. When I removed the changes I made the email resumed being sent... all email that didn't go through in the interim was then allowed to be delivered.. so nothing was lost.... but then I had no idea what order to put things in or if some settings should combine with or supercede others...