Version 1.2.1 has been released. It fixes some small bugs only. The database has not been changed but I would still advise you to uninstall your old version of KiwiComics and then install the new version this is because your database may have been corrupted.
So to summarize: upgrade only if you have no stability problems otherwise uninstall and then install the new version.
Try this version if you had problems with KiwiComics not starting up.