- create a blank new page, with name "AddNewPage" (for instance), and add the content:
- This will add the module "quick edit" in to the page, which tends to solve what you are looking for.
- add a link to this new page (AddNewPage) inside the application menu (or any other you like), through "Admin>Menu>Application Menu" (n. 42).
- Click on its tools/options icon, and add a new item with the link to your new page AddNewPage wherever you want (position 203, for what you saig in your example).
- You may need to add "feature_wiki" in sections, and "tiki_p_view" in permissions.
However, yopu can add just the module "quick edit" to your preferred column, to allow everybody add or edit a wiki page directly from there, as it works here at tw.o.
Hope it works for you.