I'm having problems with TinyMCE too.
In my case that could be due to having Oxwall installed in a subdirectory instead of the root of the website.
My gut feeling however is, that this problem you are experiencing is caused by cosmetic changes to Smarty templates in the latest version 1.2.4.
Simply post a remark pointing to this post (copy the URL of this post and paste in your remark).
Thanks for reporting back!
--Strangelove