First, did you clear the cache (core/cache/ - delete all files) before you dumped the database and files? Also, did you re-run setup after you moved the database? If not, do so. And then make sure to clear the core/cache files again. Also, clear the browser cache.
Depending on the server, you may need to set compress_css and compress_js to "off" in system settings. If you can't get to the system settings, go to the modx_system_settings table in the database and set them both to "0".
Essential: check your config files.
core/config/config.inc.php is where the major path changes will likely be set incorrectly. Re-running setup doesn't change these paths unfortunately, so go in and check each path instance. I think there are something like 6 instances of path settings in this file.
There are three other files that need checking too, if you read through the "moving your site to another server" docs, they are all listed. Usually a setting of "/core/" in these will work, as long as the other file points to the root install. Setting the path specifically should also work.
http://rtfm.modx.com/display/revolution20/Moving+Your+Site+to+a+New+Server
Once you've deployed files to the new server, you need to update the main configuration file: core/config/config.inc.php. You have to update paths to 6 different resources. Open the file and update the values for the following variables doing a find and replace:
/* PATHS */
$modx_core_path= '/path/to/modx_doc_root/core/';
$modx_processors_path= '/path/to/modx_doc_root/core/model/modx/processors/';
$modx_connectors_path= '/path/to/modx_doc_root/connectors/';
$modx_manager_path= '/path/to/modx_doc_root/manager/';
$modx_base_path= '/path/to/modx_doc_root/';
$modx_assets_path= '/path/to/modx_doc_root/assets/';
/* HOST (used for command-line PHP stuff) */
$http_host='yoursite.com';
If you are also moving your site into or out of a subfolder, be sure to update the variables such as $modx_connectors_url, $modx_manager_url, and $modx_base_url. They should generally
end with a slash (e.g., $modx_base_url='/' for a site not in a subfolder).
Permissions
Before you can edit your config file, you may need to loosen up the permissions. After you've edited it, be sure you restore the read-only permissions on the file.
There are also 3 additional configuration files that contain two PHP constants:
define('MODX_CORE_PATH', '/path/to/modx_doc_root/core/');
define('MODX_CONFIG_KEY', 'config');
/config.core.php
/connectors/config.core.php
/manager/config.core.php
Make sure you update the paths in these files as well.
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