[Plugin: Flickr Gallery] PLugin has stopped working

When I first installed this plugin it worked perfectly. I was able to use the following shortcode

[flickr-gallery mode="photoset" photoset="72157605870230826"]

to insert specific photosets into my posts.

I haven’t done anything on my site for ages apart from update plugins when updates have become available. So even though I initially started off with version 1.2.6, I’m now running the latest version and when I try and insert a photoset I get a 404 error page if I save as draft, try and publish the post and try and preview it.

My posts require the <!--more--> tag to be inserted, but I’ve done numerous tests and found that if I write a post without the <!--more--> tag, the plugin works as it should. As soon as the <!--more--> tag is inserted I get a 404 error on trying to save, publish or preview.

I’ve disabled my other plugin to see if there is a conflict, but I get the same results everytime.

Does anyone know how I can fix this – or does anyone have a download link for an earlier version so that I can backdate to a version that worked with my site?

Thanks

http://ww.wp.xz.cn/extend/plugins/flickr-gallery/