Can't access content catalogue

[yjs]

I've just installed XWD 365 Premium 64 bit, on a new machine (Windows 7). When I try to access items in the content catalogue I get:
An error has occurred in the script on this page
Line 140
Char 13
Error: Object doesn't support this property or method
Code: 0
URL: http://downloadsv12.xara.com/web/cat...viewer.js?v042

Grateful to know how to resolve this - thanks.
[edited to add that I'm using XWD 365 Premium, 64 bit - the problem persists after a complete reinstall and is also occurring with a new installation of P and G 365. Disabling firewall etc. doesn't help.]