Can you install FF in same computer in both Windows 7 and Windows 8?

IANAL but to my understanding, this is forbidden:

Here’s the quote from the Filter Forge EULA, the Grant of License section:

d). Standard License. Unless otherwise specifically provided under valid invoicing, purchase order or licensing terms accepted by Licensor in writing (e.g. trial, beta, or multiple user license as specified in a contemporaneous purchase order or agreement) granted by the Licensor upon registration of the Product (online or otherwise as provided by Licensor), Licensee is granted a non-exclusive and non-transferable license to Operate one (1) copy of the specified major version of the Product by one user account in the operating system (“User”) during the Term of this Agreement on one Client Device provided that if multiple or volume License is purchased, the number of the Client Devices and the number of permitted users shall be as provided and permitted by invoicing terms or applicable terms and conditions set forth on the Licensor’s website www.filterforge.com at the time of purchase of the License.