I've looked how you did displaying language in Maintenance/Language but I think something may not working as it should, or I misunderstood the purpose of this app.
I think the application should work like this:
There are couple of labels i.e. 'Number of Records:' label:
Then I think I should set default language in my browser (for example to German) and the label name would be automatically switched to Rekordzahl (i don't know exact translation).
I tried German and French language and nothing happens. Am I doing something wrong?
For best results, use the Firefox browser..