Rust GUI welcome / info

I would like to have a plugin, which creates a GUI Box. This GUI should be shown to to User if he connects to the server. On default it should be blank with just a button to close it. The content of the box (and maybe the size) should be configurable. If possible, i would like to use size or color codes.

Ive looked trough the pages of existing plugins, but wasnt able to find anything that fits to my needs.

 

UniversalUI for Rust | Oxide - simple, powerfull, got everything you need

 

No, it doesnt open on server connect (as i read).
I also thaught about it but i really need sth that opens on connect.
(Will test if it does)

 

Rules GUI for Rust | Oxide