Dolphin 7.0.7 langauge issues - Forum compilation

After updating many strings in Dolphin to read more naturally in English (apologies Boonex), I created a my own 'language' to prevent them from being overwritten during upgrades. Unfortunately, now experiencing the following error during forum language compilation:

Language files compilation have been failed. Please check folders permissions.

Plenty of Unity forum entries on this issue, but most are many versions (and years) old, nothing recent. Many include taking many kinds of corrective measures, many of which don't seem to work.

Anyone know how to fix this problem?

Details:

• Permissions for all folders under /public_html/modules/boonex/forum are set to 777 (see attached image).
• English has been removed as a language from the site, but still appears as a compile language in Manage Forums (see attached image) and compiles successfully.

Thanks in advance

Figured out cause of this forum language compilation failure:

the language file was not named xx.php (xx is two characters), but xx was actually 4 characters. After xx was shortened to 2 characters, compilation was successful.

Thanks