>> Error Message: Message did not meet security requirements
This is a common Shibboleth issue. I believe you will get lot of info through googling.
>> "Required attributes: Generally a nameID attributes is required. Please talk to us to generate this nameID in your Gluu Server."
In Gluu Server, we release 'TransientID' as default attribute. Google SAML might not accept 'TransientID' as required NameID; so we configure and map such NameID for our customers. [Here](https://wiki.shibboleth.net/confluence/display/SHIB2/IdPNameIdentifier) is the doc of Shibboleth how you can create such nameID manually.
>> The instructions seem very clear on the google side, but not so much on the gluu side.
Yeah? Thanks for your comment, man. What points can we include to make it more 'Gluu side'? Please feel free to suggest us...
Kind regards,
Zico