Can I use all the products of "Stuctural Enterprise perpetual "even after expiration of SELECT Subscription?
No, Structural Enterprise licenses are not perpetual. If cancelling a SELECT subscription, you choose child product licenses that together equal the value of the Structural Enterprise licenses you had on contract. Perpetual nodelocked licenses are then generated for the chosen child products instead.
Can I choose/use "STAAD.Pro Advanced" as a child product license out of the Structural Enterprise licenses after expiration of SELECT Subscription?
Yes, STAAD.Pro Advanced is one of the available child products. Please note that this license alone will consume the value of almost one entire Structural Enterprise license. You can use our Pricebook to compare the perpetual prices in your country for Structural Enterprise and the child products.