This is an elusive bug that occurred when installing a new copy of Lazy Sunday and fresh copy of the plugin fckgLite.
The script in the plugin directory did not load, i.e. script.js. This happened in both Centos and in OS X. Then I tinkered with the fckgLite code and got the script to load. Next, I cleared out the caches--dokuwiki and browser--and went back to the original code, which had previously failed, but now the script loaded correctly. This was true on both OSes.
Then I installed fresh copies of both DW and fckgL, cleared out the browser's cache (DW was of course clean) and the problem had disappeared, and despite repeated tries I could not get it to reoccur.
I had once had a similar problem on an Ubuntu server with Lemming. But I attributed it to the fact that the test server was old and slow, and that possibly the script had arrived too late.