I recently wanted to upgrade my TTX installation to the latest version, 2.3. After a little searching, I found that no one is keeping the Windows installer up-to-date. I definitely agreed with the forum poster that said they would gladly pay $50 for a commercial version of TTX.
So, lacking a commercial version and not wanting to become a Python expert, I sought another solution. After I tried a few things that failed, such as following the build instructions that come with TTX, I hit on one that worked! At least as far as I can tell, it works.
I installed the Windows version of the Adobe Font Development Kit for OpenType (AFDKO): http://www.adobe.com/devnet/opentype/afdko.html
which includes TTX. Unfortunately, this is also an older version of TTX. Knowing that TTX is a thin wrapper around the fonttools library, I replaced AFDKO's version of fonttools with the latest from TTX 2.3. The resulting TTX appears to have 2.3 functionality! I would be interested to hear from any TTX experts thoughts on what will not work with such a hack.
Since Adobe must make TTX work for both Windows and Mac as part of AFDKO, it would sure be nice if they would be willing to spend the little extra work I suspect is needed to keep it always updated to the latest TTX. Just a thought. Since they give us the AFDKO for free, I can hardly complain.