Welcome to my site. I have adjusted a script for BBC BA to help distribute custom scenarios via an exe file. It's a beta release.
You can download the current release here: http://sites.google.com/site/bbcbatools/BAScenarioInstallerv1.zip
From the Readme:
BA User Created Scenario Installer
Hi,
this is a tool to create a simple installer for user created scenarios for BA.
How to use this?
Download the zip file and extract somewhere. No special place needed and it's best to place outside of anything BA related.
Place your Mission Sub Folder in the Scenario Folder.
For example if I had created the Pegasus scenario, the Amaris_Missions subfolder had to go there.
Next adjust the Info\install.ini file and give the dialogtitle something which describes your scenario. Fill in author and version.
Next adjust the Info\readme.txt as well and maybe add a screenshot.bmp in the Info directory.
At last run BuildScenario.cmd which will create an exe file in the Outpit directory.
A big thanks go to Jordan Russell(http://www.jrsoftware.org/), the man behind the open source Inno Setup installer tool which is used for this.