Well, well. This is turning into a linux tutorial. I can see from the debugs that there is a permission issue. The directory listing seems to show the files though.
Have you checked the file permissions and ownership ? You need r (Read) and x (Execute) to change into a directory. But for the file itself you only need r permission.
As root user try this:
chmod u+rx /home/ftpuser/ftp
chmod u+r /home/ftpuser/ftp/*
chown -R ftpuser:ftpuser /home/ftpuser