I had severe problems getting tinyMCE to run after "successful" migration.
I run WordPress 3.5.1 with a myriad of plugins. The new Server runs php 5.4
I looked into the error.log of the apache server and it revealed that some plugins complained about not having access to module called CURL. (curl is a library for php to get data from other servers)
After installing php5-curl (on Debian 7.0 wheezy) all problems seem to have vanished.
Maybe this is of some help for you.