Q: Are jars from alphaver channel safe?

A: Yes, they are completely safe

Q: How do I make a server?

A: Download JRE 8 (Java Runtime), Rosepad server and then run
$ java -Xmx2G -Xms512M -jar server.jar
If you want to use bukkit plugins, try LilyBukkit
Full tutorial here

Q: How do I access hub?

A: There's no hub code in the jars, therefore you can't

Q: What's the code for Lilypad?

A: With Rosepad you can type your username into the key field and it will generate one for you. If you're using vanilla, register here

Q: Which client should I use?

A: As for now, Rosepad is the most up-to-date (and the only maintained) Lilypad client

Q: Have you seen the latest video?

A: Yes