I’m sure Joe will chime in here, but if it was me this is what I would do (not knowing what error you are actually seeing):
go back to the defaults and get it working that way first
- check the url you have set in RW for the project
- get rid of any pretty url code in your .htaccess file.
- preview the blog post page and click the default url button
- when the modal pops up (mine is white also) does the URL look correct? Click the send
- go to admin and edit a post (just add a space at the end of a line) and save it.
Once you get it working on default url’s, then tackle the pretty url settings.
FYI, if you hover over the newspaper icon in the ADMIN blog list page and click the small link icon, it will show you the permalink url. Is it correct?
EDIT: I can see the issue is that there is no postURL being saved - that happens when you hit send in the modal window of the post page in RW preview. That is the basic issue. What is the error message when you hit send?
EDIT 2: here is where the first one actually is: https://dernalandscapes.me.uk/blog/post.php?permalink=the-rain-curtain-garden This tells me that your Public blog List page and Your public Blog Post page are in the same folder (/blog). I know joe showed this in the video, I’m not sure why. I would make the post page a child page of the list page and change the name back to index.php unless you have some reason not to.