Hello,
Regarding question (1), you have choices with how you structure and submit your driver package, but you do need to include any files that are copied by your INF(s). Thus, if you are designing your INF to support multiple architectures, your
driver package should include those binaries even if you only submit HCK test results for a single architecture.
If you have a distinct INF per architecture, then you have the option of only including the binaries that are specific to that architecture in the driver package.
In terms of your HCK submission, you can choose what driver packages to include based on the OS/architecture they were tested against. With any of the options above, the Hardware Dev Center Dashboard (sysdev.microsoft.com) will validate the submission
you provide for the respective operating systems and architectures you provide in the HCK submission. In addition, the *.cat files will be created and signed according to those OS/arch pairs as well.
For the *.cat file question (2), you do not need to worry about including these files in your submission. We will create and if necessary, overwrite, any *.cat file that is required by your INF(s) with the file we sign with the final certificate.
You may contact sysdev@microsoft.com for further assistance if you have questions specific to your driver(s).