Can I Update A / CName / MX records on my Domain?

Of course you can. We presume if you are configuring to this level you know what you are configuring, otherwise you may have a none resolvable website or email that doesn't deliver. If you are un-sure, please raise a Helpdesk ticket and let us assist.

Log into your Helm Control Panel 

Click on My Domains > Domain_Name

Click on DNS Zone Editor and update as required.

For details of the options available for  Webhosting click here