There is a Mepis forum here on LQ, I suggest you spend some time there.
No doubt will lead at some point to www.mepislovers.org
- seems to be the "ordained" user site.
As for your problem, I admit I don't understand. Once installed, there is no requirement (that I have found) for the install CD to be present. My "better half", with zero Linux knowledge, uses Mepis successfully daily.
I created her user account when I did the install.