Looking for software to display and edit the .json files for Google Maps Timeline

TWO questions, really:
(1) Following Google's information included in Google's notification that it is getting rid of Timeline on the Cloud, I downloaded my previous Timeline from their Cloud servers to my cellphone (Android 14 UI 6.1).
I can see the more-or-less accurate timeline.  But editing it is next to impossible.
I can answer Yes or No when asked to verify a location.  That's the ONLY thing which consistently works.
If I click the appropriate button to either Modify a Time or Add a Visit, one of three things happens:
(A) Nothing whatsoever -- clicking the appropriate button does absolutely nothing.  The button doesn't even blink or anything to indicate that it has been clicked
(B) Clicking the button LOOKS like it's working ... but then nothing happens.
(C) I immediately get the ridiculously uninformative message "Something Went Wrong."  (I think this is the most frequent.)
And even if the timeline is correct and I don't need to make any changes, the phone version does not offer the "Snap to" (roads, sidewalks) which the online version used to offer.
Comments?  Your own experiences?  Workarounds?
MORE IMPORTANTLY:
(2) Suggestions for third-party software (Mac OS X) to display and edit the Timeline .json files.
HOPEFULLY software which has its own excellent database of roads, sidewalks, trails, and transportation lines (bus, train, airline).
Or which at least uses similar maps online
MUST HAVE "Snap to" for the various types of route listed above.
Thanks.
--
Dudley Brooks, Artistic Director
Run For Your Life! ... it's a dance company!
San Francisco