Hi, Rich.
I compiled goffice 0.10.32 and gnumeric 1.12.32 on TC10.1 64-bit. (I chose these particular versions because I have a complete Debian Stretch mirror--including source packages--and these are the versions in my mirror. I compiled the upstream tarball I grabbed from my mirror, without any of the Debian patches.)
The build steps I took are exactly what I detailed in my prior post.
I do not see the "Source ID...not found when attempting to remove it" error when I run the gnumeric 1.12.32 extension that I created. The only error I get now is this one when I open any spreadsheet:
Glib-GIO-Message: 11:37:55.659: Using the 'memory' GSettings backend. Your settings will not be saved or shared with other applications.
There are no other errors when opening or closing spreadsheets, and they open immediately. It doesn't bother me if it doesn't save my settings--I just need to view, edit, and save spreadsheets; default settings are good enough for me.