Socialize is difficult to set so post on Facebook look right. Got it working like I wanted after some problems a month or so ago, but today a post simply refused to publish
The post has a NextGen gallery, with 9 full size pictures, perhaps 15 mb all together, maybe more. Is there an issue with NextGen?
When I manually pasted the post to Facebook, no image appeared and the first few sentences of the blog also didn't apear. Usually my header image gets posted, even though it's too low and too wide. The post is global: https://www.facebook.com/owen.laws1
Afterwards I did a test post and it worked fine.
Facebook object debugger (https://developers.facebook.com/tools/debug) gave this error message for "Open Graph that should be fixed":
"The 'og:image' property should be explicitly provided, even if a value can be inferred from other tags."
I chose an image and set it as a "Featured image" in the post in the edit window, but it was apparently too small, and now also get this warning on the post, even though I (think) I removed that image:
"Provided og:image is not big enough. Please use an image that's at least 200x200 px. Image 'http://www.owenlaws.se/wp-content/gallery/131222-manifestation-nazistfritt-jamtland/img_9114.jpg' will be used instead."
The only thing I did differently than usual with this post is that I started it on my iPhone with the WordPress app, added 3 of the 9 pictures full size but realized that that would take too long so I saved as draft, and continued to work on the computer a bit later. I deleted the the pictures, finished the text, and added all 9 as a NextGen gallery (not album), that I inserted as a slide show.