Thanks to @peacemaker-ic‘s various posts, I was able to find out how to convert old CC windows

Thanks to @peacemaker-ic‘s various posts, I was able to find out how to convert old CC windows to the new system. He also mentions there’s still a possibility of Sims 4 Studio receiving a batch fix. If it turns out that a batch fix just isn’t possible, I will begin updating my windows/doors. Until then, I will probably hold off on doing so just in case a batch fix is made (since it will save A LOT of time)