Back Button, Trying to return user to previous slide

Hi All,

Someone that can help me? I´m relatively new at e-learning.

I have made my own Back, Pause & Resume buttons on every slide. The Pause & Resume work fine but the Back button with reference to the previous slide (Specific Slide no.) takes me to it but then the timeline seems to freeze & does not continue. If I use reference Previous slide then nothing happens.

Any help or advice would be greatly appreciated.

Thanks