WebHelp Previous and Next Buttons

I'm trying to force the WebHelp browse sequence buttons to behave like the forward and back buttons in a CHM. I've added the buttons and modified the java script files per the RoboWizard's instructions. The buttons show up and work correctly, but the button appearance is not consistent.

What I mean is, sometimes when navigating to the next topic the previous button will show the disabled icon and the next button will show the enabled icon. You can still click the previous button (disabled icon) to navigate to the previous topic but you can't click the next button (enabled icon) because you're at the end of the list. This behavior is inconsistent in regards to where you are in the table of contents, but it is consistent in which specific topics show which button. I've moved topics around and compiled multiple versions. The same topics show the same (incorrect) enable/disabled icons in each build.

I'm currently using the same icon for enabled and disabled as a temporary fix. Does anyone have any ideas? Thanks is advance.

Scott