Multisite Subdirectory Install – Infinite Redirect Loop

I’ve been googling and messing around for two days and none of the posts I read seemed to have helped… Below is a description of my situation.

– I host my website at nearlyfreespeech.net and registered the domain name r1ff.com with them.
– I set up a blog at https://www.r1ff.com/blog/ and it’s been running for a few months fine.
– I upgraded to 3.5 a few days ago.
– Recently I decided to set up a new blog that’s completely separated from my old blog. I turned on the MultiSite with subdirectory install. I set up the new blog at https://www.r1ff.com/blog/kzclg/ .

What I can do:
– The original blog is still working fine. I can visit it, I can access its dashboard, I can post articles and upload files, I can publish and delete posts. Everything worked.
– I can visit the network admin page and add/delete sites. That worked fine.

My problems:
1. When I visit my new blog, https://www.r1ff.com/blog/kzclg/ , I see a page with bare HTML and no CSS. Theme wasn’t applied, and it looked ugly.
2. When I visit the dashboard for my new site, https://www.r1ff.com/blog/kzclg/wp-admin , my browser tells me I’m stuck in an infinite redirect loop.

I don’t know if it matters, but my original blog was set up at /blog, coinciding with the mandatory prefix for all new blogs. Is that an issue?

For reference, here’s the content from my .htaccess

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /blog/
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /blog/index.php [L]
</IfModule>

php_value memory_limit 64M

# BEGIN WordPress

RewriteEngine On
RewriteBase /blog/
RewriteRule ^index\.php$ - [L]

# add a trailing slash to /wp-admin
RewriteRule ^([_0-9a-zA-Z-]+/)?wp-admin$ $1wp-admin/ [R=301,L]

RewriteCond %{REQUEST_FILENAME} -f [OR]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^ - [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(wp-(content|admin|includes).*) blog/$2 [L]
RewriteRule ^([_0-9a-zA-Z-]+/)?(.*\.php)$ blog/$2 [L]
RewriteRule . index.php [L]

# END WordPress

And here’s the relevant part from wp-config.php

/* Multisite */
define('WP_ALLOW_MULTISITE', true);

/* Multisite installation */

define('MULTISITE', true);
define('SUBDOMAIN_INSTALL', false);
define('DOMAIN_CURRENT_SITE', 'www.r1ff.com');
define('PATH_CURRENT_SITE', '/blog/');
define('SITE_ID_CURRENT_SITE', 1);
define('BLOG_ID_CURRENT_SITE', 1);

/* That's all, stop editing! Happy blogging. */

If I should provide more information, I’d be glad to do so.
I don’t understand .htaccess or php at all, so please be lenient on jargons.