Hello, Mark. I continue testing the 1.21 version.
The default installation seems to work; however, it does not support
formula typing, nor references nor the short url.
I see neither "short URL" nor MathJax" among the "extensions" you
syggest;
so, I insgtall again. This time, I choose all the extensions offered.
I Expected that some of them provide the required options.
The extensions seem to conflict; I get message
[6ea7a99f] 2013-04-06 14:22:46: Fatal exception of type MWException
Sincerely, Dima.