It happened to me too.
Solution: Uninstall the plugin. But offcourse you are not able to see your front end right and neither the back-end, so you should go to your mysql database find the table with the plugin, search for something like active = 1, Turn it off with active = 0. Something like that. Then you will be able to get in again into your template.
I am sure must of your problem are running around permissions in your hosting. So you should take a look there too and change permission 644 to 755. After that you are sure you will be able to upgrade your ja_plugins and etz.
So upgrade your Ja_components download the Ja_Typo Plugin again and install it, after that you will not face more problems with upgrading.
Let me know if this help you.