Why are you installing themes manually, instead of installing them from within the wordpress dashboard?
Are there any relevant error messages in /var/log/messages, /var/log/httpd/access_log or /var/log/httpd/error_log (specifically related to permissions or PHP Basedir settings?)
What version of wordpress are you using? If your wordpress version is old (to support old PHP, for example), then the new themes might not work.
If the two questions I've asked above don't point you to an actual error message, you probably want to start over and outline your configuration completely (sme version, wordpress version, wordpress installation method, wordpress updates applied, sme updates applied, other, relevant sme contribs installed, etc).