1. If your reply is on-topic, especially in the context of educational threads like tutorials, feel free to bump it with a question. Even if the tutorial is old, someone will see that you're trying and should be able to point you in the right direction. Of course if you're inclined to create a new thread that is fine too, you might even get more replies that way.
2. I believe you have to donate or rank up before you can set an avatar that will appear next to your posts. Profile pictures and avatars are seperate.
3. SRL is for OSRS, yes. AeroLib is an old, unmaintained include, using it is strongly discouraged. The recommended setup tutorial is
here, and the scripting tutorial is
here.