Create a shortcut to auto-join the group chat!

Step 1) Find your Steam.exe file or a shortcut of it.
Step 2) Create a new shortcut of it.
Step 3) Right click -> Properties.
Step 4) Under the Target field add a parameter as such... "...Steam.exe steam://friends/joinchat/103582791435116500"

There you go! A shortcut to launch both Steam and the Group Chat!

Add it to Window's Startup folder to launch upon Window's Startup!