Where are my 32bit settings "kept" after changing over to 64bit Notepad++?

[Phroneris]

Hello. First time to speak on this forum.

I had used Notepad++ 32bit and meaninglessly I tried installing 64bit version using npp.7.5.5.Installer.x64.exe.
When running, firstly the installer showed an alert saying “You are trying to install 64-bit version while 32-bit version is already installed. Would you like to remove Notepad++ 32 bit version before proceeding further? (Your custom config files will be kept)”.
I pressed Yes and expected that all or most of my existing 32bit settings would be handed over to 64bit, or at least it would export 32bit ones to somewhere and I would end up by importing them to 64bit manually, except some plugins limited in 32bit.

After the installation, I opened new 64bit Notepad++ and found almost all are reset. Preferences, styles, shortcuts, user-defined languages, macros and so on.
And I also cannot find old ones exported or evacuated anywhere.
AppData\Roaming\Notepad++ seems to be totally renewed and C:\Program Files (x86)\Notepad++ is empty except NppShell_06.dll.
I searched my computer for some setting files like functionList.xml but there are nothing special in my other folders.
Where are they kept? Or, is there anyone else that have experienced similar situation?

P.S.
Now I’ve succeeded (maybe) in rescuing a certain amount of them from weekly backup files in my external HDD, but of cause it’s not a thing that the installer did…
(I first tried “System Restore” as I didn’t know it doesn’t repairs Appdata files at all)

PC: Windows 7 64bit
Notepad++: v7.5.4 32bit -> v7.5.5 64bit