Here's a "quick and dirty" Italian translation I just did, with the help of translate.google.com.
This took me under 30 minutes for the first translation, start to finish, plus another ten or fifteen minutes to tinker. I think this file is a reasonable starting point for people who are native Italian speakers, to fix errors, search/replace for better words, etc.
First, a screenshot, with comments on the "quick and dirty" workflow I used below that.
Quick and dirty translations using Google:
translate.google.com can translate the entire default.ui.txt into a desired language, but it has a few limitations:
1. It can get confused by the use of the equal = sign, and fail to translate the word in patterns like tag=word unless there are space characters on either side of the = sign, as in tag = word. Easy to replace "=" with " = " in Notepad.
2. Likewise, words in angle < > brackets might not be translated, so those angle brackets should be set off with space characters. Easy to replace "<" with "< " and ">" with " >" in Notepad.
3. Words that are prefixed with & can be not translated. Easy to replace "&" with "& " in Notepad.
4. Google sometimes translates SQL key words and sometimes not.
5. It translates only 5000 characters at a time, and then you have to press Next to translate the next 5000 chars.
Start with default.ui.txt.
1. Open default.ui.text in Notepad.
2. Replace "=" with " = ".
3. Replace "<" with "< " and ">" with " >".
4. Replace "&" with "& ". Even better, delete all & since it is unlikely Google will handle access keys correctly.
5. In translate.google.com choose English on the left and the target language (say, Italian) on the right.
6. Copy the entire text from default.ui.txt and paste into the left side of translate.google.text.
7. It will translate the first 5000 characters. Copy those and paste into a destination ui.xx.txt file that is open in Notepad.
8. Press Next in the google translate bar to have the next 5000 characters transated. Copy those and paste into the destination ui.xx.txt file.
9. Be careful to copy all the translated characters from the first to the last. Carefully check the first and last lines for errors, where Google can mistranslate a tag that's broken up by the 5000 character limitation.
10. Make sure to save the destination ui.xx.txt file as UTF-8.
In the destination file:
Google sometimes injects extra space before / after $ when used as a bracket character.
11. Find "$ " and " $" where $ used as bracket and eliminate extra spaces, eg: $ manifold $ to $manifold$
12. Replace "& " with "&". No need to fix spaces with <> angle brackets, as google seems to remove extra spaces automatically.
13. Quickly scan down the tags to see if any have been translated. If so, replace them with the original from default.ui.txt.
14. Quickly scan down the BuilderQuery... tags to see if any SQL for those tags has been translated. If so, replace the SQL with the original English SQL from default.ui.txt.
Here's a comparison of an English query builder and my first Italian query builder before I fixed the above:
After making the fixes in step 14:
You can see from the above that Google isn't perfect. For example, sometimes it translates "component" as "componente" and sometimes it doesn't. But that's an easy fix with a careful (check each instance), case sensitive search and replace of "component" for "componente". Other small errors like that are also very easy to fix.
All the above took me 45 minutes for Italian, the first time I ever used this workflow. The actual copy/paste/copy into google took less than 20 minutes (it goes fast).