Some quick further information: I just noticed that BOTH Transforms have 'Cache Installer Files' set to True, but NEITHER actually does so. All other options from the transforms appear to apply correctly, but none of the installer files are copied to the PC.
The AIP was created using the standard:
- Msiexec /a AcroPro.msi
- Apply patches with the following command: msiexec /a <msi filename> /p <patch_file>