Combine .htaccess

I'm having a problem with 3 different .htaccess file that I would like to combine. Please see the attached files. They come from the vbseo site map vbranks and the myspace profile rewrite mods. How do i combimne them?

Internal Server Error

The server encountered an internal error or misconfiguration and was unable to complete your request. Please contact the server administrator, webmaster@infitechdesign.com and inform them of the time the error occurred, and anything you might have done that may have caused the error.
More information about this error may be available in the server error log.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.
Apache/1.3.34 Server at www.infitechdesign.com Port 80

both
php_flag highlight.string #668400
php_flag highlight.comment #668400
php_flag highlight.keyword #668400
php_flag highlight.bg #668400
php_flag highlight.default #668400
php_flag highlight.html #668400

# RewriteEngine on
# RewriteRule ^$ index.php
# RewriteRule (^[-_A-Za-z0-9\ ]*$) member.php?&username=$1
# RewriteRule ^(sitemap.*\.(xml|txt)(\.gz)?)$ vbseo_sitemap/vbseo_getsitemap.php?sitemap=$1 [L] and
php_flag highlight.string #668400
php_flag highlight.comment #668400
php_flag highlight.keyword #668400
php_flag highlight.bg #668400
php_flag highlight.default #668400
php_flag highlight.html #668400

RewriteEngine on
RewriteRule ^$ index.php
RewriteRule (^[-_A-Za-z0-9\ ]*$) member.php?&username=$1
RewriteRule ^(sitemap.*\.(xml|txt)(\.gz)?)$ vbseo_sitemap/vbseo_getsitemap.php?sitemap=$1 [L]
dont work

<edit>
Sorry i didn't read the post before this one, but in any-case the rewrite doesnt seem to work. Should i put it in
home/infitech/public_html/.htaccess where i have this:

RedirectMatch temp ^/index.php$ http://www.infitechdesign.com/forums/
or combine what i have in the forums htaccess and put it in the forums directory?
home/infitech/public_html/forums/.htaccess