Sharing to PhotoStream

The situation is like this:

- I used to take photos with my digital camera and I imported the photos to Aperture

- then for some photos (imported from d-cam) that I want to use on my iPhone/iPad, I select that photo, click 'iCloud' sharing to share it to the default 'PhotoStream'

- the photo will show up in the PhotoSteram,then I'd be able to pick it up from the PhotoStream on my iPhone/iPad and do whatever I need to do about it

*Note that in the iCloud preference, under 'My PhotoStream', I only enabled the 'Automatic Import', but not 'Automatic Upload'.

It used to work that way but some time back it stopped working. I tried stopping the 'My PhotoStream' and then restart it again but have no luck.

Any idea?

Thanks and regards,

Murphy