- Kovid suggested moving the 64bit Calibre to wherever the portable version is 'installed' and giving it a try - I am pretty sure he means the program files, not the config files.
The config data is the same for 32 bit, 64 bit and portable - the difference is only where the files are located, installed versions put the config data in AppData, the portable version puts the config data in the subfolder Calibre Settings
of wherever you have the portable version installed.
Forget the config files in AppData (they're an artefact of the 64 bit install) and they're irrelevant to what I think you're wanting to do - which is to try Kovid's suggestion.
- Copy your entire Calibre Portable folder to somewhere like C:\CalibrePortableTest
- Copy what's in C:\Program Files\Calibre2 (that's 64 bit Calibre) to C:\CalibrePortableTest\Calibre - overwrite whats there
- Try running CalibrePortableTest\Calibre\calibre.exe
If it works and it is the 64 bit version (it displays '64 bit' in the status line, I think) then you have the means to get what you want - a 64 bit portable Calibre. If it doesn't then keep using the 32bit portable from wherever you currently have it.
You'll probably want to uninstall the 64 bit version once you've got things as you would like - I think the uninstall has an option to get rid of the configuration files in AppData - if not delete them manually after the uninstall.
Hope this helps - BR
PS : you tell Calibre where to put a Library when you create it - by default I think portable puts them in wherever the program is installed. I think I'm right in saying that Portable was intended to be run off a Thumb Drive that contains the whole kit and caboodle. But AFAIK a library can be anywhere.