Need some help with my htaccess file... pls help... i need it working for my AS3

Here is my htaccess file:


RewriteEngine On
RewriteCond %{HTTP_HOST} ^(.*\.)*mydomain.com$ [NC]
RewriteCond %{SERVER_PORT} !^443$
RewriteRule ^(.*)$ https://www.mydomain.com$1 [R]

I would like to make ONLY a folder https protected, not the entire site.
How would i do it? Which changes do i need?
When i make my entire site https, my flash file get TOO big. Or at least, thats is what looks like.

Thanks,
Regards,
Leo.