Here's my solution for users to make the game portable:
1. Launch the installer and choose your portable drive as the installation location.
After this step, you should have a directory
WorldOfGoo at the root of your drive.
2. Launch notepad and copy/paste the following:
set userprofile=%cd%
set path=%path%;%cd%WorldOfGoo
cd WorldOfGoo
WorldOfGoo.exe
3. Save as 'LaunchWorldOfGoo.bat' directly at the root of your drive.
From now, you just need to double-click on this file to launch the game. Your settings will be saved on your portable drive.
4. If you want to use your previous settings, copy the directory
c:\documents and settings\<user name>\Local Settings\Application Data\2DBoy at the root of your portable drive.
Note that
c:\documents and settings\<user name>\Local Settings is a hidden folder. So to go to that folder you can either select the option in explorer to display hidden file then browse to the folder ; or type
c:\documents and settings\<user name>\Local Settings in the adress bar of your explorer.
Of course you need to replace
<user name> by your real user name.
5. If you want Windows to automatically suggest to launch the game when you plug your drive, launch notepad and copy/paste the following:
[Autorun]
Open=LaunchWorldOfGoo.bat
Icon=WorldOfGoo\WorldOfGoo.exe
Title=WorldOfGoo
Action=Launch WorldOfGoo
Shell=Shell00
Shell\Shell00=Launch WorldOfGoo
Shell\Shell00\Command=LaunchWorldOfGoo.bat
6. Save as autorun.inf directly at the root of your portable drive.
You can now make hidden all the previous files and folders of your portable drive (not required, just for a neat installation). All you need to launch the game is to plug your drive, wait the Windows popup then hit enter. You can also double-click on the drive in the explorer. To browse in your drive with explorer, you have to click on the disk in the left tree of explorer (click on the button 'Folders' in the toolbar if it's not visible).