It depends on how you have your repository structure and what you are trying to accomplish. We prefer to do "pre-commit" reviews, which in the world of DVCS really means "pre-push". DVCS's are nicer in this environment (when compared to traditional SCMs) because they have built-in functionality for saving your local changes and getting your workspace back so you can work on something else.
If you want to do post-push reviews, the ideal workflow depends heavily on your repository structure. For example, let's assume a repository structure that looks like the one discussed in this article on Git repository layouts. In this case, you may want to review changes that are being merged into
develop. Individual commits on feature branches may not make sense to review. Obviously all
hotfixes must also be reviewed along with the merges into
If instead you have a single integration branch where people are checking in directly, you would want to review all pushes to that branch. That is probably slightly less efficient, but could still work. In this environment, you would have to ensure that all the changes that had been pushed are reviewed before you cut a release. That can be trickier.
As for b) the only thing I would suggest is emailing SmartBear support (firstname.lastname@example.org) directly. We'll (yes, I work for SmartBear) be happy to help you work out your path issues, but there's not enough information in this question to fix your issue. The normal process is to just run the installer and everything just works. Apparently something has gone wrong in that process.