Q. If I add a device to a map, then I add that same device to another map, will that end up using two licenses? Or just the single as it's a single device?
A. If two devices are added which are identical in every way (IP address, probe type, parameter values, etc.), and the probe type is Ping or one of the SNMP family of probes, then they should be detected as being identical, in which case they will "share" polling and be counted together as only a single device against your license maximum. If they are not absolutely identical, or are some other type of probe, this does not apply and they will count individually against your license maximum.