Hello PJMS -
Apologies on not getting back to you sooner on your prior post. It is unclear what may be occurring for you with the support form, we did have a brief issue with the form for part of a day not too long ago, but this issue was resolved. I suggest that you first try clearing the cache of your browser to ensure that it has not cached the support case page erroneously and then try again. If the issue persists, please try using an alternate browser and let us know both the browsers and the results.
As for the issue with Returns, at present we do not have a way to specify international returns on our listing creation page, but we are aware of the changes that eBay has made and are working on a resolution.
On new listings, you do need to have the category applied to the listing for the Checkout Options area to provide you with the appropriate Returns fields. If you have the category selected and then opt to have Returns Accepted the fields for the other details become available.
I will update this thread as soon as more information becomes available regarding international returns.