That looks good to me.

1) Check your server, is it Linux?
2) Check your file and folder permission
3) Make sure clean browser cache and reload the page

I haven't received any report from other users, but I will give a try later.

OK, check the syntax and rules for image at the bottom of page http://paulgu.com/wiki/Drop_Down_Menu_Series

Read instruction on page http://paulgu.com/wiki/Drop_Down_Menu_Series for image setup.

Hide any menus, search the forum for the answer.

I had this answer in the forum.

Mediawiki has made a lot of core updates, you need to apply latest GuMaxDD skin for latest wiki...

Use any editor like notepad...

Sorry I was away for a little while, you should see them now....

You need to meet wiki syntax for external links...

I'm not sure what type of page image that you are talking about... the image inside wiki page?