You can use ePAD as a research PACS. In fact, ePAD uses dcm4chee as its DICOM back end, which is a full-fledged robust PACS. You do DICOM send from your clinical PACS to ePAD, and you can store hundreds of studies (you just need to make sure to allocate sufficient disk space to the ePAD virtual machine you have). In addition, if you want your ePAD research PACS to have de-identified images, you can use CTP, pushing images from your PACS to CTP, which in turn will di-identify images and send them onto ePAD. That’s how we do things at Stanford.
That should be possible. We are primarily using XNAT for user and project management. Plus we store high-level information about users and their associated studies. We do not currently store any image information in XNAT (though at may change in the future). If you just want to use your XNAT with ePAD to utilize the users and projects defined in your XNAT instance, then that would be possible with not too much work. Let us know when you want to try this and we can help. (Though, the host-only mode configuration of your current VM installation does not allow calls outside the VM, so you would have to set up your VM differently.) However, accessing and annotating DICOM images in your XNAT instance (if you have any) with ePAD is not currently possible. We may ultimately provide this functionality - but for the moment we are assuming that DICOM images are stored in a PACS.
You can interactively download AIM files using ePAD. Go to the Annotation tab, select the annotations you want to download, and click on the Download button. Programmatically the AIM resources can be accessed via the REST API.