Problem solved. I'm on a mac. First I followed these instructions to show the hidden files on my hard drive: in Finder, open up your Macintosh HD folder. Press Command+Shift+Dot. Your hidden files will become visible. After that I went to my hard drive, then users/(my username)/ Library/ Application Support/ Blender/ 2.82/ config/ and then I dragged the ...
There is a file called recent-files.txt that is saved where the config files are.
If you edit that with the new paths you should be fine.
For the location of the file refer to this post:
Where is the startup file stored?
I am not using mac, but I think I can help you.
First go to Edit->Preferences->Keymap.
And then select Key-Binding:
Now you can search for the shortcut that you want (in this case you will search for ".") and change it to whatever you want.
I hope it works for you.