I found this link:
Consumer Product Registration
I had to register my login information. After that you are prompted to view your currently registered items and or registered a new item.
I don't own Mares items but my sister does. I have to have her try it too. I think she was having issues with it as well.
The link to login is:
http://oms.mares.com/cpr/login.jsp
I just spoke to my sister about it and she said that she was not given any options for her regulator. It just showed computers.
Shortly after her saying that, I found this page:
https://oms1.head.com/oms/mares.do
It has a contact tab on it on the top right along with a help link. The help link doesn't look like it works, but the contact link appears to maybe work. It looks like it is an up to date site.
© 2011 MARES is at the bottom right.
I found this PDF for Mares Recall on a Nemo Computer. It says: "The telephone number for the Diving Division is 203 855 0631; fax 203 866 9573; website
www.mares.com. For HEAD USA information, log on to www.head.com"
I called and found that Mares is owned by HEAD or that their parent company is HEAD.
I thought that the OMS portion of Mares was owned by Ocean Management System, then discovered that Head OMS is Head Online Management Systems which is their online system they use for registration and product information.
I called the above number and they told me that I had to register products through the mail and that they do not do them online. The girl I spoke with told me to forward registration cards to:
Mares
902 Clint Moore
Boca Raton, FL 33487
Hope this helps!