Al menos en el Pro te permiten 2.
No, pero eso ya es cosa tuya.
The end user license agreement (EULA) of Native Instruments' products allows the simultaneous installation on two computers (three computers for all versions of KORE and KOMPLETE), as long as only one installation is used at any given time. It is not necessary to "deactivate" an existing installation to activate the product on a further machine, but due to the license agreement it is required to uninstall the product from the previously used computer.
Please note that Native Instruments reserves the right to disable an account or serial number if it has reason to believe that the license agreement is violated.