[DiapDealer]

The only thing that might give me pause in your Process Monitor log is the indication that the names of files or folder might be changing in Sigil's preferences folder.

C:\Users\HP\AppData\Local\sigil-ebook\sigil NOTIFY ENUM DIR Filter: FILE_NOTIFY_CHANGE_FILE_NAME, FILE_NOTIFY_CHANGE_DIR_NAME

It might be nothing more than temporary lock-files being created/removed, but I wouldn't know without creating some logs of my own to be sure it wasn't crash-related.

But clearly something is corrupting your Sigil ini files. Not being able to access them, or read their contents, would be the only reason your keyboard shortcuts would revert to the new-installation defaults. Have you tried exempting Sigil's program and preferences folders from any anti(virus|malware) realtime scanning?

I'm also wondering if you have corruption lingering in your ini files from Sigil's failed attempts to convert its ini files to utf-8 (Sigil versions 0.9.11 and 0.9.12)? Have you backed up your ini files, deleted them and started from scratch to see if that resolves the crashing? If so, you may need to recreate your custom keyboard shortcuts and saved searches manually--as copy/pasting data from your old ones might very well result in copying corrupted data right back in.