I have uploaded a ZIP archive with the files of CMS by FTP (automatic installation does not suit me). But the ‘Extrackt’ right-button command does not work. First of all, it refuses to extract files to the same directory with the archive file. Is it caused by the file size? And does this restriction exist in other plan (not only in the free one)?
This is probably because the file is too big. Try the tutorial below to help you unzip! Also, there is no restriction to what can be extracted on premium.
There is a limit of the size of files uploadable via File Manager and also extraction too, best to use FTP and use the unzipper.php script.
To avoid limits like this upgrade to premium where there are no limitations.