[Plugin: GRAND Flash Album Gallery] Errors

I am receiving the following error after updating the skins of the new gallery plugin. Can you please assist me in what I might do to resolve this?

Warning: unlink(/home/r****/public_html/wp-content/plugins/flagallery-skins/stylishgrey/colors.php) [function.unlink]: Permission denied in /home/r****/public_html/wp-content/plugins/flash-album-gallery/lib/core.php on line 263

Warning: unlink(/home/r****/public_html/wp-content/plugins/flagallery-skins/stylishgrey/gallery.swf) [function.unlink]: Permission denied in /home/r****/public_html/wp-content/plugins/flash-album-gallery/lib/core.php on line 263

Warning: unlink(/home/r****/public_html/wp-content/plugins/flagallery-skins/stylishgrey/screenshot.png) [function.unlink]: Permission denied in /home/r****/public_html/wp-content/plugins/flash-album-gallery/lib/core.php on line 263

Warning: unlink(/home/r****/public_html/wp-content/plugins/flagallery-skins/stylishgrey/settings.php) [function.unlink]: Permission denied in /home/r****/public_html/wp-content/plugins/flash-album-gallery/lib/core.php on line 263

Warning: unlink(/home/r****/public_html/wp-content/plugins/flagallery-skins/stylishgrey/stylishgrey.php) [function.unlink]: Permission denied in /home/r****/public_html/wp-content/plugins/flash-album-gallery/lib/core.php on line 263

Warning: unlink(/home/r****/public_html/wp-content/plugins/flagallery-skins/stylishgrey/xml.php) [function.unlink]: Permission denied in /home/r****/public_html/wp-content/plugins/flash-album-gallery/lib/core.php on line 263

http://wordpress.org/extend/plugins/flash-album-gallery/