We recommend that you always use the most recent version of JOverseer. To revert to this, try uninstalling JOverseer, then installing a fresh version from our website.
However, if you really want to use a previous version, then once you have installed it, you can edit the regedit file as follows to make it work:
search/run regedit
Go to Computer\HKEY_CURRENT_USER\Software\JavaSoft\Prefs\org\joverseer\ui\
Delete the row: recent/Games
But please be careful, as making a mistake when editing regedit can mess up your machine. GSI take no responsiblility for anything that might go wrong if you attempt this!
Also, note that games created in version 1.18.17 onwards will not load in previous versions. So if you do roll back to an earlier version, you will then need to create a new game file and re-import the results for each game you play.
