[Waiting] .tns isn't recognized

[JumbaWumbaFumba]

whenever I try to open a tns file, it says that it doesn't support the document format, I have reinstalled ndless multiple times and nothing has worked, please help

[critor]

Where do the .tns files in question come from ? Any url ?

And, is there a "Ndless installed" message in green in the top-left corner of the screen ?

Thanks.