How I tested this:
1. I installed the current (beta) build of MC which includes this "fix", opened it once, and closed it again.
2. I installed the Amazon MP3 Downloader (had never been previously installed on this machine).
3. I opened the Amazon MP3 Downloader and set the Folder option to C:\test\
4. I opened MC, but didn't do anything with the interface, and then closed MC again.
5. After a few minutes, I checked the setting in the Amazon MP3 Downloader. It had changed back to C:\Users\<USERNAME>\Music\Amazon MP3.
Then...
1. I opened MC and navigated to Services & Plugins -> Amazon. MC popped up the dialog, and I chose "No" and the "don't bother me" checkbox. I left MC running.
2. I opened and reset the setting in the Amazon MP3 Downloader back to C:\test\
3. I left both the Amazon MP3 Downloader and MC running for a long time (more than an hour), just sitting there.
4. I came back, and checked the setting in the downloader, and (hurray) it was still set to C:\test\
5. I closed the Amazon MP3 Downloader and opened it again. No change.
6. I closed MC and re-opened it (with the downloader still running). No change.
7. I closed the downloader and opened and closed MC. No change.
8. I left the Downloader running a LONG time again (more than an hour, MC not open) and checked it. No change.
Then...
I went into the Windows Registry and modified these keys:
[HKEY_CURRENT_USER\Software\JRiver\Media Center 14\Properties\Confirm]
"Ask About Amazon Downloader Configuration"=dword:00000001
"Ask About Amazon Downloader Configuration (Last Value)"="No"
And changed them to:
[HKEY_CURRENT_USER\Software\JRiver\Media Center 14\Properties\Confirm]
"Ask About Amazon Downloader Configuration"=dword:00000000
"Ask About Amazon Downloader Configuration (Last Value)"="Yes"
Then, I...
1. Opened the Amazon MP3 Downloader, and immediately checked the setting. Still fine at C:\test\
2. Reopened MC. Left it sitting at the "Start" Page.
3. Checked the Amazon MP3 Downloader setting. It was back to C:\Users\<USERNAME>\Music\Amazon MP3.
So, as you can see, with the option set to "Yes" (which is the default immediately after MC is installed), you do not have to navigate to the tree item, where you will see the pop-up, in order to have the action applied.
In other words, it still changes the setting without asking. The only difference is that you can force it to ask if you know where to go, and then you can make it stop in the future (but by the time you get there, the setting will have already changed).