Nginx Support

I have wordpress on a nginx server and I have these errors:

Your backup folder MIGHT be visible to the public
To correct this issue, move the .htaccess file from wp-content/plugins/wp-dbmanager to /home/content/45/8604645/html/wp-content/backup-db

(I saw and the folder is not public. As I use nginx I can’t upload any .htaccess file…)

And in Backup BD i have this error:
Backup folder does NOT exist. Please create ‘backup-db’ folder in ‘/var/www/wp-content’ folder and CHMOD it to ‘777’ or change the location of the backup folder under DB Option.
Backup folder is NOT writable. Please CHMOD it to ‘777’.

When I change the folder to 777, I think your plugin changes the folder again to 775…

Thanks for the help in advance…
Regards

http://wordpress.org/extend/plugins/wp-dbmanager/