I made a copy of the Everything.ini file before I went through the process.
Replacing the default Everything.ini file with the one from a week ago DID preserve my Color Themes! But...for some reason the Custom Filter disappeared.
Your custom filters are stored outside Everything.ini. They are in a file named Filters.csv.
You can use Everything to search for this Filters.csv file.
It is a plain text file, so you can view it in - for example - Notepad to see if it contains your custom filters.
If you found the right one, you can put it in the folder where your Everything.ini is. For most peaople that will be the c:\users\<your username>\appdata\roaming\Everything folder.
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