Installer, application manager and camera raw plug in issues

Hi - I need help.

I'm running on Windows 7. I have just upgraded Photoshop to CS5.5 from CS4 (on my laptop not a creative cloud version). I have since uninstalled Photoshop CS4. I was trying to install the camera raw plug in 6.7.1 but it would not install and I got a message saying that the application manager was damaged and to download it again. I have downloaded the application manager file but cannot install it. I am getting the "installer failed to initilize" message. I've read through the forums on this and cannot find a solution.

I have extracted the file so I am not trying to open a zip file. I have downloaded a second time to a different location and tried installing again while logged into creative cloud but got the same message. I saw the comment about deleting the Adobe/OOBE folder and trying again but was wary about doing this as I don't know what this folder is. Can someone tell me what this is and why I would delete it?

I don't think I had this issue before I uninstalled CS4. I think I had already downloaded a camera raw plug in for that version. So I am wondering if deleting CS4 caused the issue.

I then downloaded CS6 cloud version thinking that perhaps I would get application manager installed correctly within that. I have now been able to install the camera raw plug in and this is now working in CS5.5 but strangely still cannot run the setup.exe for the application manager (So perhaps it is just a problem with Installer?).

Can someone tell me if application manager is just relevant for cloud based products or is it required for desktop versions as well? Could creative cloud be interferring with my desktop version? Where can I find the application manager files? If I uninstall CS6 will I have the same problem with application manager not working in future? I do not really want to use a cloud based version (CS6) and don't want to keep unnecessary programs on my laptop.I signed up to Creative Cloud when both desktop and cloud versions were supported and may not continue when my subscription expires.

To fix this problem without CS6 do I need to reinstall CS5.5? (To do this I will have to reinstall CS4 as it was an upgrade version). Would just reinstalling CS4 fix the problem? Can I just reinstall the application manager part of either of these or is there a simpler solution?

Thanks in advance as I am not super tecchie and am running out of ideas.