Connecting MetaAttributes to MetaAssociations
A MetaAssociation cannot be connected to a text type attribute. An attribute can be connected to one or several MetaAssociations. The "Order" attribute is connected to all MetaAssociations.

A "Text" type attribute on a link is only accessible with certain tools such as the explorer, and not by others (diagrams, etc.).
To connect an attribute to a MetaAssociation:
1. In the Properties window of a MetaAssociation, select the MetaAttribute tab.
2. Click
Connect 
and select the MetaAttribute.

You can select several MetaAttributes.
3. Click Connect.
The selected MetaAttributes appear in the list of MetaAttributes of the MetaAssociation.