1. Yes. A single Process license will cover 1 concurrent unattended desktop flow.
2. This would be needed if you have a cloud flow that does not run a desktop flow. In such a case, you would need to have a Process license for each flow like that. If your cloud flows do call desktop flows, you're good to go.
3. You do not need a Premium license in addition to the Process license. But if the user does not have a Premium license, attended flows will not be available, including running the flow from the PAD console directly on the machine.
4. If you have a machine group and a single license, only one flow will still run anyway at the same time, regardless of the number of machines in the group. If you want to run more than one desktop flow concurrently, you need a Process license for each concurrent run slot.
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