SlideNumber Widget in Captivate 8

It has been a while that that old widget is no longer included, you must have skipped some versions .

You'll need the system variables cpInfoCurrentSlide and cpInfoSlideCount, both from the category Movie Information,look at the table in: System variables in Captivate 8 - Captivate blog

Insert a text container (shape or caption) on the first slide, time it for the rest of the project (always on top). In that container insert the text that want and include the variables using the X button in the character part of the Properties panel (while you are in editing mode). On the stage it will look like:

   Slide $$cpInfoCurrentSlide$$ / $$cpInfoSlideCount$$

You could type everything in as well, but be careful because all names are case sensitive! It is safer to use the X button and choose the variable from a dropdown list.

Why do you need a widget for this.  If all you want to do is display a slide number you can do that with Variables displayed in a text box or Smart Shape.