Is not good have to do 15 posts only for download a plugin that u want! I'm here for install a plugin but i can't only bc i need 15 posts. They're a lot!
You can find some topics that you're interested in in the forum and give your opinions about some.. You'll be more at ease getting those credits. The main reason of that is to avoid leechers
The quieter you become, the more you are able to hear ..
I would say 15 posts are reasonable good number, because how long i have been here, i saw people just going to flood with posts or new threads on first day to get points mostly on 6th or more some people start recognise the spaming person and report about it. The smart ones would reach it by answering the threads, mostly the Introduction thread to welcome new people. Or answer just random threads like "What is your favorite pet", "Which hero from Overwatch you main" and etc.
