I understand that in order to use Audacity with ASIO4ALL one must first download the Audacity source code. Unfortunately the instructions for doing this are spectacularly unhelpful (at least for a person with limited technical ability). A page recommended that I download from an SVN source as these are much more likely to build out-of-the-box on Windows, so I followed a link to the SVN repository. There is a list of files there, but no further instructions about what to do next. I would appreciate some detailed instructions. Thanks.
Instructions for building on Windows are here: http://wiki.audacityteam.org/wiki/Developing_On_Windows
Be warned, building software from the source code on Windows may be difficult. (I use Linux so I’ll not be much help other than pointing you to the right documentation)