Where can I find the presets for HDRI Studio Rig?
Perpetual License Holders: Presets can be found in the updated version of HDRI Studio Rig. You can install the new updated version for free through your account page. Grab your updated version from the "Downloads" section in your Customer Account.
Please note, perpetual plugins are no longer available to purchase. They will receive one more update with Cinema 4D and will be technically supported until January 1, 2022.