Can't find the local original files where they should be

I have a Windows 10 laptop with Lightroom (CC) installed.  I've imported about 20,000 photos and they have all uploaded to the cloud.  In Edit > Preferences > Local storage I checked the "Store a copy of all originals at the specified location".   I did not check the "Store a copy of all Smart previews on C:"  I set the cache size to 50% of free space.  It shows about 250Gb required space.  I did all this at least three months ago.  Cloud storage says "Synced and backed up" and shows about 219Gb used.

1) I want to backup my originals and other information (catalog?) to an external drive.  When I look at the "Storage location for originals:" and click the Browse button it opens a folder at the specified location: "C:\Users\[MyName]\AppData\Local\Adobe\Lightroom CC\Data".  But if I open Windows File Explorer and browse to that location there is no Lightroom CC folder.  (I have "Show hidden folders" and "Show system files" turned on in File Explorer.)  If I try to find it by copying and pasting the path from Lightroom to File Explorer I get an error saying it can't find it.  After a lot of looking I think I found it in C:\Users\[MyName]\AppData\Local\Packages\Ad0beSystemsIncorporated.AdobeLightroom_ynb6jyjzte8ga\LocalCache\Local\Adobe\Lightroom CC .  (I had to put a "0" in the path because the forum editor won't allow "Ad0beSystems" in the body text with a "o" for whatever reason.)  The size of the folder matches the size shown in Lightroom Preferences; 250Gb.  Is this path confusion something caused by Windows 10 voodoo?  Is Adobe intentionally hiding the location?  It does not give me a good feeling about knowing where my stuff is all the time for backup purposes.

2) Will I get any performance improvement by moving the originals location to somewhere with a shorter path?  Assuming it will really move the photos.

3)  Will I get better performance if I turn on "Store a copy of all Smart previews on C:" even though I have the originals local?

4)  When I am in Lightroom scrolling through the photos in Detail view using the track pad it will stall for awhile and usually skip photos, this seems to be worse with raw photos.  If I scroll to a video it will stop scrolling completely with the track pad.  The arrow buttons and mouse wheel work ok.  I don't have a problem with the track pad in any other situation, only Lightroom.  Editing is responsive and quick enough but just browsing through the photos is a pain.

Thanks for your help.