Is the Adobe Color Engine replaceable with the ICM2.0 engine from Windows and vice versa?

The Adobe Color Engine (ACE) and the Windows Image Color Management (ICM) are two APIs that serve similar purposes but in different environments. ACE is required to set up and modify ICC profiles in PDF documents and the APDFL environment. ICM is required to set up and manipulate ICC profiles in the Windows environment.

Commonly neither is used. The document specifies profiles for the colors within itself, and the display device specifies a profile for its own rendering. Adobe PDF Library will harmonize those profiles, converting colors as needed.

In some cases, documents or devices do not contain color profiles. ACE can be used to establish default profiles for documents, and ICM can be used to specify a profile for a device.

If you want to write an application that honors render intent—the color profile included in the PDF document, and presumably intended by the person that created the PDF document—you may want to use ICM to set a color profile contained in the document as the profile to be used by the output device.