The merlin.nsi file is a installer build script.  To build the installer you need to have the NSIS tools installed on your machine.  After building using avalon:dist, just right ckick on the installer, select "Compile NSIS Script" and the resulting install exe is placed in the merlin/target directory.

Problems:

1. MELRIN_HOME is created properly but the PATH does not seem to be 
   updated properly to include %MERLIN_HOME%/bin

2. Currently no checks to see if MERLIN_HOME is already defined, and 
   in particular if MERLIN_HOME is defined as a system scoped env variable
   we should not be redefining it in user scope.

Steve.