Tell me please, what instruction is correct:
http://wordpress.org/extend/plugins/nextgen-gallery/installation/
or
http://alexrabe.de/wordpress-plugins/nextgen-gallery/
???
in first instr there are folders - wp-content/plugins/nextgen-gallery & WordPress Upload folder
in second - wp-content/plugins/nggallery & into the NextGEN gallery folder
what is right???
