Well everything is in the same diagram of the same profile.
Maybe i totally misunderstand.
I used as example this pic i found on the website for icons.

To be sure i'm understanding correctly:
Here, MyElements is the toolbox, linking the item MyStereo through the attribute.
MyTech is the profile. I don't understand what means (My Elements) before the toolbox name.
Everything is in the same profile package.
My project is like that:
Model
- <<profile>> OEAProfile
- - OEAProfile //The class diagram where i edit the toolbox.
- - <<stereotype>> OEAProfile::OEAClass(UML::Class) //Item
- - <<stereotype>> OEAProfile::OEAInstance(UML::Class) //Item
- - <<stereotype>> OEAProfile::OEAToolbox //Toolbox
- - <<metaclass>> ToolboxPage
In OEAProfile::OEAToolbox, i have two attributes refering to the two items.
What am i missing? I'm quite lost with that kind of development...
Thank you for your help,
SJ.