Is this course purely linear? If so, then you could set just one variable equal to a specific value (maybe combined with page count). Then, you know to show the timer right away if the variable is greater than X. That's a pain to maintain, though, but it would be simple to implement.
I know that some people find use in searching for a string within a variable. Perhaps you could add to a string variable a certain value, such as "%001" for the first page. When each page is run, you check to see if that string is contained in the variable. If so, then you show the Next button. If not, then you keep the Next button hidden (which I presume becomes visible because of another action when the page is shown). I suggest an Else tab that adds the string to the variable. That way, the action checks for the string, and if it's not there, it adds it, saving you extra actions and ensuring that your variable does not choke when someone visits a page 20 times and generates "%044" over and over again.
Kevin
