No .exe created with install

I've been searching and troubleshooting this for hours, to no avail. No doubt the answer is simple, but it escapes me.

I created a 2gb truecrypt virtual encrypted drive.
I then downloaded and installed Pidgin-OTR 3.2 (from the PidginPortable page here) onto this clean volume.

It reports that all went well, but there is no .exe file to be found. The only things it does create are:

M:\PortableApps\PidginPortable

This directory is empty, except for two sub-directories, which have their own sub-directories:

• -App
  ---Pidgin
  -----Locale
  -----Plugins
• -Other
  ---Source

These directories all contain the files one would expect, but nowhere is there any .exe file from which I can launch the ap.

What am I missing?