If you get an error 'parameter value policy error' when changing your domains nameservers this typically means the nameservers are not responding for the domain or they are not designated as being authorative for your domain . To correct this you must first add your domain to the hosting server/ hosting plan that is using these nameservers and then update your domains nameservers.
The nameservers must have also have NS records that point to the nameservers themselves, this designates them as being the authorative nameservers for the domain. Please note, this is an IEDR restriction on the use of nameservers for .IE domains, not a Myhost.ie policy.