Since this is not my plugins issue i will let you address it on your end.
However i will say that i do fully support languages. For the plugin language itself it requires that users donate language builds to the plugin just like any plugin - noone does that hardly anymore so again not my issue.
For the recaptcha language part of it, i again do support languages. The issue is with oxwall vrs recaptcha because as you can see in my recaptchafield class file i notated the reason why sometimes it may not match.
Here is that comment in the file:
/*
********************************************************************
* the site and recaptcha dont use same lang code style
* so matching the value to the site selection does not always work
* there may be times that this feature will not change the lang code
* for the recaptcha because the codes dont match
********************************************************************
*/
There are so many dif variations of for example en, EN, en-us, en-US, EN-us, E-us, US-e and so on for other languages that it would be a major undertaking to capture them all and i did not feel i could keep the plugin affordable in doing so. Especially when the issue effects very few people. This is proven by the fact that you are the only one that has an issue with this out of tons of other users.
Now that issue could be resolved if you can let me know what language you are having issue with and i can check to see what code i use and you can check what code the recaptcha uses on your end and we see what the dif is. Maybe it is a minor issue, but again i do support all major languages meaning most popular and used languages.
If you want to try to test this, just reply to my support area for the plugin. There is no need to take up any more of this support area (which is not for my plugin) in discussing my plugin.
Thanks