Access to Author Archives

So my weblog currently publishes author archives to: %a/%y/%m/index.html, and does so statically. I can log into my FTP server, and see that the file tree and index files do, in fact, exist. I can check the chmod settings, and though the directories and files started out at 666 for some reason, I have changed them to 755. And yet, despite all of this, I cannot access the files. For example, http://www.wallsofthecity.net/linoge/2009/06/ *should* work - I can see the index file, plain as day, in my FTP program - and yet it does not.

So, two questions: First, how do I get archives to be automatically published at chmod 755 as opposed to 666? And, second, how do I get the author archive directories to show their index.html files? These are the only archives that give me problems... individual posts, categorical, and date-based all work just fine.

If it helps, my .htaccess file has the following code:
-----
## %%%%%%% Movable Type generated this part; don't remove this line! %%%%%%%
# Disable fancy indexes, so mtview.php gets a chance...
Options -Indexes +SymLinksIfOwnerMatch

# The mod_rewrite solution is the preferred way to invoke
# dynamic pages, because of its flexibility.

# Add mtview.php to the list of DirectoryIndex options, listing it last,
# so it is invoked only if the common choices aren't present...

DirectoryIndex index.php index.html index.htm default.htm default.html default.asp /mtview.php

RewriteEngine on

# don't serve mtview.php if the request is for a real directory
# (allows the DirectoryIndex lookup to function)
RewriteCond %{REQUEST_FILENAME} !-d

# don't serve mtview.php if the request is for a real file
# (allows the actual file to be served)
RewriteCond %{REQUEST_FILENAME} !-f
# anything else is handed to mtview.php for resolution
RewriteRule ^(.*)$ /mtview.php [L,QSA]
-----

Thanks for any help! :)