I got it working on Windows 7. I had to use AN220SW to create a custom driver with the Pololu PID then I could successfully run AN144SW. Here are the steps.
From Windows XP - connect the Oragutan Programmer
1- Download and unzip AN220SW and AN144SW from Si Labs website.
2- Run the program CustomUSBDriverWizard.exe in the AN220SW folder.
3- 1st screen - Select Virtual COM Port Installation, select Customized Executable Installer, click next, click next.
4- Select Windows XP/Vista/S2K3/7, click next.
5- Change the PID listed to 803B, click next until it’s finished, click finish.
6- Go to C:\Silabs\MCU\CustomCP210xDriverInstall and run CP210xVCPInstaller.exe, click Install. This will install the new driver. Restart the computer.
7- Run the program CP210xSetIDs.exe in the AN144SW folder.
8- Change the Pid to EA60 and click the check box next to Pid.
9- Press the “Program Device” button. Done on XP.
From Windows 7
10- Download and install the signed CP210x VCP driver from the Si Labs website.
11- Connect the modified Orangutan Programmer and the driver should install successfully.