Actually, it turns out my problem *wasn't* from port blocking. It was the first thing everyone on the Yunohost forums suggested though. There was no automated tool suggesting otherwise, so I still had to research which ports needed to be open and find a tool to test it to realize it was another problem.
I would have found the real issue sooner if it just tested and reported if necessary ports were open on install and on installing apps that needed new ports.
A system like that would also know which ports *should* be open and could then help you lock down your firewall by asking about ports that are open that it doesn't need.