I'd love to help. One of my first webquests was on Powerpoint, and I taught a PD workshop on how to do it. IY has been so long ago, and I don't think I could find the files if it killed me.
First you "Save as" a webpage.
If you then go to mydocs, whereever you saved it, you can doubleclick the explorer icon. You will see the titles on the left are clickable. The titles are of what you titled each page. If you didn't use the "Click to add title box" and you really don't want to, then you could put one in but make the font the same color as the background. I don't think that is necessary.
At any point you want to have a link to another slide to aid in the direction of the webquest, just type the desired text, highlight it, insert hyperlink, but now choose "place in doc" or look for a slide number.
I hope this helps. This is shooting from the hip. After long I decided it wasn't a clean product. IF you already have a ppt, then it makes sense.
I used PowerPoint and Mind Mapper 2008 Pro. MM produces its own presentations or PP. With MM you can have the additional goal of a memory helper/jogger design, ideal for teaching.