Problems with module version

I encountered some strange behaviour when playing around with a custom (local) module and its version.
It seems like the latest module version, who has ever been installed, will remain in key_value > schema.

I uninstalled my module after I applied version 8.0.0.2 to it to "test" the update_hooks, which failed. Then trying to set 8.0.0.0 and re-enabling it again, didn't work. The old version number (.0.2) is still present in table "key_value" > schema and the desired update hooks won't run again.

Which flags in {module}.info.yml or any other configuration are related to the module version?
And how to update the schema value?

Another thing: I updated D8 from 8.0.0 to 8.0.1 by replacing the core, but no database updates were "tracked" within /update.php or "drush updb". But, there are updates in core modules, which didn't get applied @see file block_content.install > block_content_update_8001: there must be a field "block_content.revision_translation_affected", but it does not exist...