The format in which TimePanic saves its data tends to change with each new release. These changes are necessary to introduce new features or to improve the internal structure of the data. When a new version of TimePanic is started for the first time after an upgrade, it converts the existing data automatically under the hood to the new format if necessary.
This automatic data upgrade is supported from any previous release, all the way back to version 1.0. You will not lose any data when you upgrade. That said, it is strongly recommended that you back up your TimePanic data before you start the upgrade.
To be on the safe side, create a backup of your data. Download the new version to your computer and run the setup.
The setup will detect an existing installation and upgrade it automatically. If necessary, your data are converted to the new format when the new version is started for the first time.
If you are having trouble with the 64-bit version, you can go back to the 32-bit version. The setup programs support sidegrading from the 32-bit version to the 64-bit version, and vice versa.