Hmm . . . I'm about out of ideas. You could try turning off the compress_js and compress_css Settings, but I doubt if it will help.
Since we're grasping at straws here, you might try deleting *all* cookies in the browser in case you missed one and delete all files in the core/cache directory again.
I can't remember if you've checked the path in the modx_workspaces table, but if not, it's worth a try and I'd triple-check core/config/config.inc.php and all the paths in all four config files.
If there is a timezone set in php.ini, you need to set the MODX timezone setting to match (put timezone in the search box in System Settings).
Since you can download the packages, it's unlikely to be a problem with cURL, mod_security, or file/directory permissions.
Is there anything in the error log?
The only other thing I can think of is a file missing or corrupted in the transfer, or an old file that somehow didn't get overwritten when you unzipped things.
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