To your first question, FR is an awesome solution to monitor web applications. Its like time machine that lets you go back and see exactly what happened and more importantly THE WHY which no one can tell you inside your application.
To solve your problem, can you please clarify somethings about your environment setup. What version of FR did you try to install? Is it windows/linux/MAC and more importantly is CF service running as local account or do you have an account setup to run CF services?
Can you share the screenshot about permissions that you mention in your email. This tells me you might have Linux or Mac but I could be wrong.
In my experience ( windows background ), lets say CF services run based of app\cfaccount domain account, then this user needs to have permissions on C:\ColdFusion10 as well as C:\FusionReactor installation folder. This is a must.
Also, please share the link for your instance, sometimes wrong portnumber or a simple missing piece can stop the page from displaying.
Hope this helps. Before I end, I do not work for FR but I use the tool day in day out and it is nothing short of excellence. Once you use it , you cannot imagine life without it just like a cell phone or GPS.
Someone from FR team will help you out, they are a great team.
Thanks,
Good Night.