The render to texture blueprint never unwraps more than 1 material because the first iteration of the for loop is wired up to the return node, resulting in a short circuit. Instead, the return node should be connected to the for loop’s completed pin.
Hello aoakenfoArchiact -
Thank you for your report. This issue has been resolved in 4.11. If it reoccurs for you, please let us know here.
Eric Ketchum