Thank you very much for a detailed explanation about your infrastructure and Veeam MP use case.
Usage of Veeam MP v7 in such a scenario is possible, but depends on your requirements. If you don't need separate Veeam MP licenses for each customer, you can have VE service and UI installed internally in your network and then it can manage data collection via VPN for collectors installed on gateways, each collector should be in a separate monitoring group, so that collection jobs are not jumping between them in case of one collector failure.
If you want to have separate license file for each customer, then you have to deploy VE service on geteways, in this case you have to install VE without some of the v7 features (because they require SDK) and I'm afraid that for such a request you have to contact our tech support team (http://cp.veeam.com
), they'll provide you with instructions on what is needed and how to do that.
And of course the best way to go is to use full Management Servers, they could require more ports to be opened, but our collector scale much better on Management Server compared to a Gateway and all v7 features are going to be available.
Let me know if you have any other questions.