Wetmike,
Try this.
On your momento, sync your library to google Spreadsheet.
On your friend's phone, under the phone setting, log in your google account. Un-sync everything. We just need your account log in.
Then, open your friend's momento, tap + to add new library.
Choose add from Google Drive.
choose your sync database.
Once added, wait for all data to be synced including photos.
After syncing is done. Unlink your friend's memento from your google account.
then, under phone setting, log out your google account.
This way, your friend will get all your data + photos. But he won't get new update if you have key in new data.
Optionally if you trust your friend, you can leave your google account log on.
Another option is to create a new google account ( seperated from your private account) that you share with your friend and use that to sync the data.
Hope this is helpful :-)
mok | matsuru
-Malaysia-