I have found a problem upgrading from v3.0.6 to 3.0.7 - there are no instructions on how to do this, and it appears the wrong download is listed at the website (it is the full component).
Support is not commercial, therefore it is understandable that the developer does not want individual emails. However, we are told to post in the forum - but it is (at time of writing) not possible to register for an account.
So a bit frustrating, despite the usefulness of the component. If I can get these issues resolved I will definitely look to continue using Simple Review.
Sorry I posted the wrong upgrade link on the blog (the correct file was on the JoomlaCode homepage), I have corrected the blog post to point to the correct file. You can unzip it and follow the instructions. There are some nice new features, so I hope you can upgrade to 3.0.7 and then to 3.0.8 without issue.
The forum registration is a case of bad timing, I only disabled it yesterday and it will be back up within a week. I was experiencing a very, very large amount of spam. It takes a large amount of time to deal with spam and the new attacks made it impossible for me to keep up and work on the component. I hope you can understand this temporary measure.
Keep up the good work.