I opened an issue at https://github.com/titoBouzout/SideBarEnhancements/issues/41 asking for improvements to the read-me so that people can take full advantage of this useful package without struggling to configure it.
It also contains my (hopefully correct) findings on the specifics and potential pitfalls of the F12 and Open With features.
While written in part from the perspective of OS X, I hope they are useful in general.