pkg_jem_5alpha_J6 fails to install on Joomla 6.0.2

Joomal V6.0.2 - PHP 8.4.6   pkg_jem_5alpha_J6

 

After installation fail 3 DB problems

Database version (4.3.2) does not match manifest version (4.4.0).
Database update version (5.0.0-alpha) does not match JEM version ().
Table 'tcre_jem_events' has the wrong type or attributes for column 'author_ip' with type varchar(45). (From file 4.4.0.sql.)
Table 'tcre_jem_venues' has the wrong type or attributes for column 'author_ip' with type varchar(45). (From file 4.4.0.sql.)
Table 'tcre_jem_register' has the wrong type or attributes for column 'uip' with type varchar(45). (From file 4.4.0.sql.)
35 database changes were checked.
65 database changes did not alter table structure and were skipped.

Thank you for testing this alpha version and for your feedback. This version lays the groundwork for upcoming changes in JEM, as Joomla 6 introduces API changes that affect the JEM core. It is an draft (not finished), but it is important to start testing it.

Please note that we are currently focused on the JEM 4.4.0 release, which includes many commits since version 4.3.4 and will serve as base (master) for future JEM versions with Joomla 6 support.

User testing of the JEM 4.4.0 release candidates is very valuable to help us polish details. Our priority is to release the new version soon (within about a week).

Thanks a lot for testing and sending your reports. Every comment helps us make JEM better.

I had to restore my V6 testsite from backup to repair the inconsystencies in the DB.

Was this caused by JEM 5 alpha?
Is JEM unable to be uninstalled, or does the uninstallation fail to complete?

If so, I will take note of it and investigate the issue.

Was caused bij JEM5 installation

Unable to uninstall  ....  XML file not found

It might be not clear from de screen copy in the base topic but also the install complained about missing XML installation file.
The text is in dutch, so I'm translating below :

Jinstaller: :Install: can not find Joomla! XML installation file
Jinstaller: :Install: can not find XML installation file
Jinstaller: :Install: SQL fault  Invalid JSON text in argument 1 to function json_set: "The document is empty."at position 0.
Extension installation is stopped.
Package installation: There was an error while installing the extension: com_jem.zip

I had a clean Joomla! 6.02 with the pkg_jem_5alpha_J6
I set the global setting to clean DB on uninstall = yes
Then I uninstalled without any problems.
But during the new install I got:

JInstaller: :Install: Can't find Joomla XML setup file.JInstaller: :Install: Can't find XML setup file.JInstaller: :Install: Error SQL Duplicate column name 'emailacljl'Extension installation stopped.Package Install: There was an error installing an extension: com_jem.zip