So I've used SS for new websites but I've never installed SS after the entire website was up and running. Is it possible to install SS without having to start from scratch? Is there any risk to trying install SS and having the installation fail? I'm very new to setting up CMS so please bear with me.
Can you clarify, "installing after entire website up and running" are you installing another SS install on the same site? Or do you want to install in a sub directory of another system?
The install should all work fine, give it a go and if there are issues, post em here.