Unused files report - RoboHelp 8

First of all, I am so pleased that Adobe has issued the fix for the RoboHelp 8 "early November" bug! (If Adobe were in Minnesota, all the bugs are generally dead by November  )
I have loaded the new 8.0.2 service release and am carefully following Peter's instructions under "Opening RoboHelp Projects" - "Service Release 8.0.2." I have a few questions at this point, mainly about Unused Files. (By the way, my RH project is working great.)

I have run the "Unused Files" report in my large online help project (i.e., a project that's been around many years, which we update twice a year, so we do a lot of adding, replacing, and deleting of images and topics). There was quite a list of files in this report. When I spot-checked several of the files, it seems that they were, in fact, obsolete, and therefore, are correctly appearing in the Unused Files Report.

1. Is it a good idea to delete the files listed in the Unused Files Report?

    (I must confess that I've been working on this inherited project for two years and I haven't yet checked this report and therefore haven't yet done this "clean-up" of unused files.) I suspect the files listed in this report are topics and images that we've deleted from the RH project, but just haven't yet done the final step of deleting from Windows Explorer.

2. Should I delete file types that I'm not familiar with?

    I'm comfortable deleting image files and htm files because I know what they are. However, I'm not really comfortable deleting these types of files listed in the Unused Files Report:

     - thumbs.db

     - xxx help.hhc_backup

     - xxx help. hhk_backup

     - xxx help.hhp

     - xxx .hhp_backup

     - $rhvariable$.htm

     - ehelp.xml

3. If my RoboHelp HTML project is working great after having completed Peter's steps 1 and 2 (i.e., check for broken links and unused files), I suspect that I can stop there, and do not need to do steps 3-5 (i.e., backing up and deleting CPD file)? Note: This is the project that suffered two hits in the past few weeks from the RH8 bug: the first time I rescued it by using Peter's HHP file method; and the second time - about a week later - I rescued it by opening my clean day-old back-up and importing the new topics and images into it. And the project has been working well since then.

Thank you very much. And thanks again to Peter, whose great instructions and support enabled us to proceed with our work during RoboHelp 8's unstable weeks.