Welcome to this community andyP.
I concur with everything said so far, and yes, you would be wise to heed that.
Corner Pass has been done in heavy winter conditions without full blown climbing gear. A lot of material already exists on this site, on the pass and the entire route. There are detailed write-ups on both passes, pictures, GPS data downloads, and lengthy forum discussions (also on winter conditions). To keep track of the more useful links, I have tagged them on Delicous with the tag "Centenary-Hut-Corner-Pass-Mafadi-Leslies-Pass". Currently there are 21 bookmarks under this topic. See:
www.delicious.com/intrepid_ve/Centenary-Hut-Corner-Pass-Mafadi-Leslies-Pass
Have a look through those links and if there are any further questions, feel free to ask. And we always enjoy hearing how it went afterwards.