4
What he mean, you should take the full package not only the upgrade package, overwrite all your files (exlude mainfile.php) and make an upgrade with the full package. Take care, make first a backup of all files and database, check the folder and files you must chmod (example file include/license.php, exapample the folder outside the root xoopsdata(caches and configs with subfolders) and follow now the upgrade instructions.
Greets