or you sure you or using the correct user name and password that your hosting provider gave you to log into cpanel,because this is always used also for your ftp , your folders should be 755 except for folders, ow_pluginfiles, ow_static, ow_userfiles they should be set to 777,if it still wont except ,try putting your domain in were it says localhost ,I am surprized you can access any of your site if you have all your folders set to 705 permission .Before you mess about with your settings back up your db ,and download your config file and all your members profile photos just encase anything goes wrong ,when installing any plugin .Some hosts wont let you use 777 permissions like my host ,but your folders well or should still work using 755
you can man update your plugins see http://docs.oxwall.org/install:update