To find the text you want to change, go to Configuration > Site Settings > Select "Language"
In the setting which says the following:
Show translation value or key. (use "key" to debug translations, "translation" to show actual translated value. "key title text" to show the key as a title tag around the text content)
Click Edit and Select "Key"
Reload the page that you want to change the text on and you will see the text has changed to whats in the images below
They are the translation "keys", you can use those to easily find the correct section in the translations area of the admin control panel.
Click on edit and change it to what you want, once finished, change the 1st section above back to "translation".
If you're logged in as admin, files will always download automatically, unless you've added a new page in Configuration > Manage Download Pages
Click the "Set Download Page To User Type" button to add a page.
Then when visiting a file download url you'll get the download page.