Hello Dominique,
I lost my taks for the last two years but after two weeks I found a good former .sqlite file.
I managed to restore it on another phone (temporary) in another account (temporary) with Calengoo trial.
I manually check all the things between the repaired old and the found database on the phones, so that the temporary phone contains all the old and new things now. Then I made a backup so I had a CORRECT .sqlite.
But, as you may know, the trial version has a newer version on Google Play than the one we can buy. When I try to restore it on my phone I get an error. I uninstall the purchased version and installed the trial to keep maintaining my things.
I would not mind to buy Calengoo again but I think that does not solve the incompatibility. :-(
What can I do? After 4 days I cannot continue my calendar...
Regards,
Zoli