As a contribution to the Dolphin community. I'm here to show you how to translate the Orca forum within Dolphin to your own language. Because I had a hard time to get it done and I just figured it out, so I think this will be helpful for others.
Assuming you already install Forum mod, installed foreign language file for your website, and when you switch to your language you will see all the [L] [L]s stuff in the forum, you go to Manage Forum to try to compile the language because you thought you have your language file installed, but you don't see that option, only Compile Lang RU, Compile Lang En showing.
So, first of all you go to Admin Control Panel, then go to Settings->Language Settings, then type this _bx_forum in the text box and hit ENTER on your keyboard, that will list all the lang keys for the forum. click on EDIT to edit the language key for other languages accordingly (see attached picture). and click SAVE after you're done with the editing.
That's not enough, after you're done editing all the _bx_forum keys, only the top of the forum is translated, the forum itself is still having [L] [L]s stuff if you view in a foreign language.
The second step is you need to use FTP and Cpanel to copy this file and rename it to your standard language code. (e.g German should have the file named de.php):
public_html/YourDomain.com/modules/boonex/forum/integrations/base/langs/en.php
(or you can browse to the Dolphin folder on your computer at \Dolphin-v.7.1.4\modules\boonex\forum\integrations\base\langs\en.php to rename that file to your standard language name, e.g Russian has the code of RU so that file should be renamed to ru.php).
so now open that new file whatever.php (the whatever should be 2 letters represent the official lang code as said above, format should be xx.php where xx= your foreign lang code).
Then edit line by line, from top to bottom, or from line # 7 to the end if you use a code editor, below is portion of my own lang file for the forum, where the text in orange is the translated text. You can put anything in there you like, but just keep the format the same.
'Forums Index' => 'Tổng Đàn',
'Forums' => 'Đại Cao Lầu',
'Forum' => 'Đàm Đạo',
'Topics' => 'Topics',
'Topic' => 'Topic',
'Orca Forum' => ':: Đàm Đạo',
After you're done translating you should click SAVE Changes or something like that in Cpanel file manager, or SAVE if you're working the file on your local drive, then use FTP to upload that new file xx.php to this folder on the server:
public_html/YourDomain.com/modules/boonex/forum/integrations/base/langs/
After all done, you now go to forum and click on Manage Forum, you should see the Compile Lang:xx option (where xx is your new language file you just uploaded from the steps above). click on Compile Language:XX then a confirmation pop up lets you know that the lang has been successfully compiled.
Go back to Admin Control Panel---Tools---Cache--Clear All Cache .
Now you have successfully translated your Dolphin/Orca forum.