It is possible to shift between a MySQL and a a SQLite database.
Roel has put this on the Forum :
Backup your MySQL calendar database via the admin's database page and download the backup file.
Install LuxCal 4.4.0L (SQLite) in any web-accessible folder.
From the toolbox section of the downloaded zip-file upload the file "lctools.php"
Start this file with your browser (so URL: www.yourplace.xxx/calendar/lctools.php)
Select the last action: "Import calendar backup file of a previous LuxCal version"
As source file select the backup file of your MySQL backup.
Select the destination calendar.
Hit the Import button.
Done!
Good luck.
Roel
It shows how to shift from a MySQL to a SQLite database.
You can of course also do the opposite.