Please note that the SSIS is officially restarting. We will be undergoing a reform of the group's structure to make it more appealing to the public. Please try to be active in the porcess of making the group better.
formats.js is used both on the server and on the client. The client needs it to know what formats to display for the format chooser, and for the ladder. The server needs it to know what rules to enforce when you select a format.
As for port forwarding, you're most likely also using the wrong IP address. After port forwarding, to connect to your server from the internet, you'll need your public IP address (in other words, the IP address of your router). Services such as whatismyip.org will tell you.
Yes, it's possible to host PS on Heroku. I just spent the last few hours figuring it out. Host it there and connect to:
Unfortunately, customizing the client (things like the tier list) is currently not possible. This is something I've been trying to think of a way to do both securely and without losing large amounts of performance, and it seems like I'm going to have to give up on at least one of those two. Oh, well. It's a long-term goal.
If you want your server to be available to the outside world, you must configure any routers between your server and the outside internet correctly - specifically, you must port-forward PS's port (by default, this is TCP port 8000).