For showcase you can use share your experience. I will change the description / title to include showcase to make it easier.
As for Knowledge Base / FAQ, I agree there are many re-occurring errors. It would be nice to collect them all and centralise as you suggest. In fact, the true value of a forum is extracting the knowledge for re-use. The challenge is the time. We did start doing this by updating the Wiki's FAQ and instructions and currently this is the logical place.
If you can think of some additional ways, please feedback and if you are aware of some re-occurring errors pls link to them and we will update the wiki.
Thanks for your help in answering a number of the forum threads...