[JWait]

You can find txt_conditions_customer in the languages section in admin.
You can also edit the text of "terms and conditions" by using that as a filter term.

Go to "Languages" and in the upper left there will be a drop down menu that says "Language: select one". When you select your language the page should refresh and you will be presented with two boxes, "Select topic:" and "Apply Filter:". Put some text in the "apply filter" box (like "terms conditions") as mentioned above. You should see several options to edit that contain those terms. Choose the one you want to edit and when you are satisfied scroll to the button that says "update all" and click it.