Formatting Lost when accessing site from other hosts on my LAN

Formatting Lost when accessing site from other hosts on my LAN. Have had an email exchange with you guys, still having issue. I changed the wp-config.php file adding the following at the end:-

define('WP_HOME','http://wiki.doamin.com');define('WP_SITEURL','http://wiki.domain.com');

The site is viewable from the box itself that hosts the IIS site using http://wiki.domain.com, but from other boxes on my LAN, the formatting is still lost when going to that URL.
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Futher details:-

Before any changes when on the server that hosts the site:-

http://localhost/wordpress/wp-login.php
this gets me to the login page

after log in I am brought here: -
http://localhost/wordpress/wp-admin/

My wiki is here:-
http://localhost/wordpress/

All working fine.

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Before any changes, from any other box on my LAN:-

http://10.20.41.200/wordpress
Gets me to my Wiki but the formatting is lost.

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After adding the two lines below and when on the same server that hosts the site:-

http://wiki.domain.com/wordpress
gets me to my wiki, with good formatting

http://wiki.domain.com/wordpress/wp-login.php
Gets me the login page with no formatting.
Logging in gets a .404

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After adding the two lines mentioned above to my wp-config.php and when on any other box on my LAN:-
http://wiki.domain.com/wordpress
Gets me to my wiki, but still no formatting.

http://wiki.domain.com/wordpress/wp-login.php
this gets me to the login page, no formatting

logging in gets a .404

Please assist.

Thanks

Colin