Yea, because open-source software is famous for having well-designed, easy-to-use comprehensive instructions.
It often sucks, certainly. But there is one compelling advantage, in the case of unusual stuff such as this. The developers themselves are happy to talk about and answer questions around their tools. And open source tools tend to attract hobbyists that do things for fun, and are happy talking about what they do, and not just commercial developers that won't publicly say a word.
So with open source tools you're much more likely to find blog posts, forums and so on with information to help you along. There's a chance there's be people out there that had the same trouble you do, and wrote about it in public. With commercial tools - and especially tools with a userbase in the hundreds rather than tens or hundreds of thousands - there may simply be no public information out there at all beyond the docs written by the provider.