Image / Link popup not working?

[robinmarek]

Using CMSMS 1.5.4

I've been showing someone round CMSMS and they are working on a Mac, as am I, and when I click the insert image button, the popup comes up fine and works.

However when he clicks it, the popup comes up but there is a blank screen? The same happens for inserting links, etc.

Any ideas what could be causing this, as I am stumped?!

Thanks

[robinmarek]

Anyone? 

[Dr.CSS]

If you both use a MAC and the same browser then he must have a JS blocker or something in his browser...