It's me again. I just played with mine wishlist some more and thought you might benefit from what I did - it will at least give you a starting point. I changed things up a little bit from what the readme file said, and the link that I put at the top of my index page is a bit different than what a true-blue Zenner would probably due, but I am rookie, so bare with me.
First, for the link at the top of the page (where your home, my account, log in/out and checkout links are), I put just a plain "hard link" to the wishlist 'summary' page. So, in the includes/templates/your-template/common?tpl_header, I sneaked a line in on line 75:
I also went to the "My Account Page" and put the same string of code in there, so customers will see a link to their wishlists when they view the things on their account. This file is at: includes/templates/your-template/templates/account_default.php.
Then, I took the code that the author gave (specifically for this area) which is for adding items to a wishlist, and added it to my product_info page, as it made more sense to have a hyperlink to add to the list there, and a link to view the list up at the top. Changing this into a button would not be hard to do (you could copy the instructions for this task from (I beleive) the "hints and tips" mod - One of the add ons that I have installed on my product page came w/additional instructions to make the link a button, I can't remember which one, you can look at my site if you want - sorry!
Anyway, this is the code for ADDING an item to the wishlist, which after the buyer clicks the link to add the item they are directed to the list itself. I added this to: includes/templates/your-template/templates/product_info_display.php. I put mine on line 249, so it would be at the bottom underneath all of my buttons.
Finally, I remember a little more on the .css with this mod. You need to edit the stylesheet that this author provided with the package if you need it to match your site. Most of the stylesheet contains basic things, there are only a few lines with colors on them, you should be able to weed through that quickly. It's in the download at: templates/classic/css.
I know this doesn't exactly address your post 100% but hopefully it will get you started on the right path to where you need to go to get this add on working for you. It's really a very detailed wishlist - I had no idea until I started playing with it today.
Good luck!
Jeanne
PS. My site is not yet live, so you can come over and play if you want to see these changes in action.
http://www.scrapbooksuppliesdirect.com/shopping - If you register to test, please use a generic or silly name so I know it's okay to delete it before we go live.