I've been able to make the slide control in FMP 13 invisible. When selecting the different options in the Inspector's appearance tab, try checking for this setting but first select each option in the upper most drop down (which selects for different parts of the slide control) in turn to check for this setting
I was able to achieve this by setting the following to have a solid background (white in my case).
- Slide Control
- Slide Control: Panel
I then had to hide nav dots too. Obviously I removed borders too.
Hope this helps.