Hi mrbert
Sounds like you have a suitable approach... experiment and have fun...!
If you install the \catalogue folder (in GALLERY_FILES_BASIC) you get the gallery product type, the display will look much the same as a normal product regarding the product lists. You need to apply the sql patch GALLERY_TYPE_ADMIN_PATCH_SQL.txt which is in the same folder.
Unfortunately most beginners meeting zencart are confused because of all the different things. Basically for using contributions you need to know how to apply an sql patch to update the database with new tables, and roughly how the template system works, and of course how to upload files.
Most contribs give you the files to upload in a provided \cart or \catalogue folder, and the sql patch which is necessary if alterations are required to database.
The second stage after uploading files to give basic gallery version is the EXTRA_GALLERY_FILES_ALBUM_COLUMNS folder. Uploading those files creates roughly the display type you see in my site demo.
Especially with the extra files, The Image Handler 2 (search in the forum and downloads) folder 1_IMAGE_HANDLER_2.0_zc137 _FOR_GALLERY is an optional thing but it enables you to just upload one bigger image, image handler then auto creates the smaller images. Afraid you need to read the included information, I apologise but its hard enough explaing in the Readme files even in English :), if you don't have full English you are at a disadvantage.
Regarding image handler 2, if you propose using that then get the ordinary (zencart contributions) download first, and run it inside a test cart, then you will see firstly how to set it up, secondly how to use it. Then it will be easier to see what my version (in my gallery contribution IMAGE_HANDLER_2.0_zc137 _FOR_GALLERY folder) should be doing and why.
Really I would not recommend expecting just to install the second 'extra' gallery files if you are a complete beginner. For instance, you need to understand that the gallery display (album) lists only switch to 'column' (grid) mode if its a gallery product category, which means you need to manually set each category you have put gallery pictures in as 'only gallery product type' in admin for that category setup.
But we were all complete beginners at one time, we had to learn by reading forum posts and other information, for instance the new book on how to use zencart. You learn by experience, and with a test cart it does not matter if it gets messed up.
And yes, stick the fetish pictures in a separate subgallery so you don't surprise people :). Its simple really, what I call a subgallery is actually just a zencart 'category'. So you can create many separate galleries all under one main heading 'gallery', galleries are just product categories or subcategories.
One quirk of galleries is that, same as zencart, you don't mix loose products alomgside existing categories.
Ideally create one main category, then within that create subgalleries, put your pics only in the subgalleries not in the main category because they won't get displayed even though admin says they exist.
Hope this answers some questions, the gallery contrib is work in progress, it works but you might need to fiddle around with the advanced version specially setting up for using image handler 2..