Timing the entrance of the player buttons.

Technically that can be done by initially hiding the Next button at the start of each slide's timeline and then change the next button's state to Normal when the timeline ends. Keep in mind that if the Next button is hidden, the Previous button will move further to the right. You might want to think about having the Next button initially shown as Disabled instead. 

Trigger to change state of prev & next buttons to hidden when timeline starts.

Trigger to change state to normal when timeline ends

Or as Michael says, maybe have them as disabled at start to prevent any jumping around.

Thanks guys. 

It looks like they are the only options. I was hoping i could set it as a general setting for the course as a whole but never mind. Thanks for your time 

Put the triggers in your slide master Howie, that should work for you

You could also try putting the triggers that 'turn on/off' the player buttons on the master slide.

The master slide is perfect. Michael. If i set as disabled is there any way of changing the disabled state of the buttons?

You mean the look&feel of the built-in buttons? You can change and texlables of hose buttons in the Player properties dialog. See here for some info.

When I change the state to disabled, it changes the button colour for the period it's changed to disabled to a  rather unsightly colour. I know how to change the button colours using the player. The issue i have is that it doesn't offer disabled as an option when doing so

Hi Howie! 

I can't see what you are describing, of course, but I thought it might be helpful if you understood the behavior of the disabled button.