It irks me when people solve a problem and do not paste the solution for others to gain. So, for those interested, here is the answer from the ticket I submitted.
"If you preview the slides individually, it's expected to have the previous button disabled. However, if you preview or publish the entire project or scene, the previous buttons on your slides without layers are enabled."
This is exactly what was happening. I was previewing the slides individually and the PREVIOUS button was disabled. However, when the entire scene was previewed, the PREVIOUS button was just as it should be.
Cleo, thank you for taking the time to fully explain the situation!
