The "exclusive" part might refer to the fact that Amos is not included with the standard SPSS Statistics 21 license. Amos is an additional module that requires a separate license or a specific bundle (e.g., the "SPSS Statistics with Amos" bundle).
You cannot run 32-bit plugins on the 64-bit version. Verify your organization’s macro library before installing. ibm spss statistics v21 x32bit x64bit and amos exclusive
It sounds like you're looking for an overview or download guide for the suite, specifically highlighting the Amos module and its 32-bit/64-bit compatibility. IBM SPSS Statistics v21 Overview The "exclusive" part might refer to the fact
A standout feature for v21, allowing you to build more accurate models from uncertain inputs and assess risk. ibm spss statistics v21 x32bit x64bit and amos exclusive