Hello,
Thank you for access!
I've found that a strange thing is happening on your server (i'm not able to reproduce it on mine).
The dot "." for latitude and longitude is replaced by a comma "," on storing event... this is the reason of the NaN returned by Google script API...
Really weird...
I've installed a version with a patch to ensure there's no comma but a dot in the stored value.
Now it seems to work!
Could you test it with all your event if it's ok ? (maybe some,you will be to set again address first).
In case other users have the same issue (but system not changed there since a long time, and no other such report until now, so maybe an osilated issue due to something on the server...), i attached here the version with the patch.
Best regards,
Cyril