RewriteCond %{REQUEST_FILENAME} /twatch 
RewriteRule (.*) - [L]
RewriteEngine On
RewriteBase /
이하생략

식으로 추가하시면 어떨까 싶습니다.

하위에 다른 프로그램 설치해뒀었는데 .htaccess 수정 위치를 바꾸니 되긴되더군요. twatch 될지 모르겠습니다만...

1.5.4
RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_FILENAME} /abc
RewriteRule (.*) - [L]

1.6 B2
RewriteCond %{REQUEST_FILENAME} /abc
RewriteRule (.*) - [L]
RewriteEngine On
RewriteBase /

제꺼 htaccess랑 내용이 좀 다른것 같아요.

#<IfModule mod_url.c>
#CheckURL Off
#</IfModule>
RewriteEngine On
RewriteBase /
RewriteCond %{ENV:REDIRECT_SURI} !^$
RewriteRule (.*) - [L]
RewriteCond %{REQUEST_FILENAME} -d
RewriteRule ^(.+[^/])$ $1/ [L]
RewriteCond %{REQUEST_FILENAME} !-d [OR]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^(.*)$ rewrite.php [L,QSA]

1.5.4
RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_FILENAME} /abc
RewriteRule (.*) - [L]

1.6 B2
RewriteCond %{REQUEST_FILENAME} /abc
RewriteRule (.*) - [L]
RewriteEngine On
RewriteBase /