Yup, you nailed it. This is something that is required so that the translator can leave an item as not translated if it hasn't been completed. Generally I try to get the people translating to do this.
Can I automate it or I must 500 times click checkbox then button Save then select next item?
No, you actually have to do this. I have considered adding a mechanism as I have had to do this a number of times myself. Just FYI, you can start at the top and do a Ctrl+Down Arrow then a Ctrl+T. That combination will speed things up, but at the moment there isn't a "set all" action.