Here is a recipe for installing Leo from scratch on Windows (Win7 tested). The only prerequisites are command line wget in PATH and an internet connection.

About 50mb of files are downloaded and 200mb consumed when done.

Open a command prompt and run:

mkdir X:\testing
pushd X:\testing

wget -O apt.exe --no-clobber http://download.osgeo.org/osgeo4w/x86/release/apt/apt-r1193M.exe
SET OSGEO4W_ROOT=%~dp0\root
apt setup
apt update
apt install pyqt4 sip

call root\osgeo4w.bat

wget --no-check-certificate http://gist.github.com/maphew/5393935/raw/install-pip.py
python install-pip.py GO
python install-pip.py GO

pip install -i https://testpypi.python.org/pypi leo-editor

python apps\Python27\Scripts\leo

After this the directory X:\testing\root can be renamed and/or moved anywhere.

To run leo in future sessions, simply call x:\path\to\root\osgeo4w.bat python apps\Python27\Scripts\leo, either as a batch file or windows shortcut.

IMPORTANT NOTE - this is just a proof of concept. It pulls together a couple of my different projects, and is very satisfying in that regard (yay! they work!), but is not ready for prime time. Feedback welcome.

(((this is a post in progress, see this thread for more)))