First of all let me start by saying this tool is absolutely impressive and very, very useful
I've found a discussion in the forum about the possibility of describing parallel messages.
Apparently the functionality was partially available, but unfinished. Key part was agreeing on the syntax.
I've tried the functionality on latest build and it seems to be still there:
Alice -> Bob: Authentication Request
Charlie-> Bob: Authentication Request
So, is there a decision on the syntax?
Is there a way of removing the box boundary? (or making it less obvious)?