Is your website already accessible so that you could post the address here?
Changing the format of the permalink – you mean in Settings -> Permalink? I think that is the wrong place. The permalink is the format of links of individual posts (and archives). You decide there if you want to have there parts of the publishing date etc. It is not the place for a redirection – therefore the name permalink.
This plugin works differently:
- A visitor goes to a URL that is the URL of your blog (or a page on it), plus appended “?redirect_to=random” (or something else at the end)
- The plugin turns that URL into another one, depending on that “redirect_to” parameter. In your case, the URL of a random post. (Actually, that now is a permalink.).
- The visitor will be redirected to that post (through its permalink), and only now the theme becomes active.
So the first step you need to check, if you type the address of your blog (e.g. the home page) into a browser, append “?redirect_to=random”, press return, if it now goes to a random post. Please check and confirm, or post the blog address here.
Then, if that works, you want to supply that modified link to your visitors. You could
- Send it to them by email
- Add a menu item, as described above
- Simply enter it as a link behind a text or a button
- Do some complicated PHP stuff that results in that link
I tried now the Juniper theme, and it does not remove ? from links. Here all works as expected. So, where exactly did you use the link with the “?redirect_to=…”? In a post? In a page? In a menu?
PS: You cannot create a new custom permalink to include the “?redirect_to=random”. If the permalink would contain a redirection, then the resulting permalink would again redirect, never ending.