Our system requirements are the same as HCL Domino.    

Wizardry and a DLL.  We're moving items that have particular headers from SpamSentinel.  The SpamSentinel Solution for any given platform, HCL Domino included, is to run our components as a native process. So there is no need to modify your mail template.  But if you ever had the need to, and didn't know how, we offer consulting for your HCL Notes and Domino system.

The installation takes time based on where you're located on the network. Our installer runs from your workstation's HCL Notes client, so if you're on the network where your servers are, it's pretty fast. If you're working from home due to covid and your entire neighborhood is watching HULU, it may take a bit longer.

Yes. We're modifying your extmgr_addins, so a reboot is required. However, you don't have to restart right after the install. Just know that it's enabled after the restart.

Live bodies.  Ex:  If you're a business that has 15 people, and you decided to give them each their own HCL Domino Server you'd still just pay for the 15 users.  No individual server costs.

Have at it, we have SpamSentinel for Microsoft Exchange Server.  Not only will your license transfer with you, we'll help port your lists over to the new platform.  We even do consulting which includes mail migration from HCL Domino to Microsoft Exchange Server