Newbie here. I tried searching at reallusion website, but can't find what allow export under Content Management is for.
Would anyone be so kind to explain what it's for?

Normally if content is not selected for export. Then that content can only be used within the program itself.

Making an item available for export means the purchaser can export it out of the program to other programs like ZBrush, unity, Maya, unreal, etc. 

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92% of original size (was 546x16) - Click to enlarge

So, export would in Cartoon Animator 4 mean, export to PSD right? Thanks!

I would assume so, but that's only an assumption of course. I do not have Cartoon Animator. I only have iClone and CC3. Hopefully another member or a Staff member could tell you definitively. 

Reallusion Marketplace Store
Content Store Featured Developer Page

92% of original size (was 546x16) - Click to enlarge

I had that same issue. Today I went back to all my orders and redownloaded with the smart download option. Spent 10 min checking everything I needed. Opened up Iclone7 and cc3 and opened the search for items and there they were. some on Iclone and some on cc3 . But check all your stuff at 1 time now with downloader. And if your missing files right click on the main item un instal and then re install. seems to be some bugs they need to work out

It's in the CC3 and IClone program. built in now. Turn on you iclone 7 and you'll see smart load. hit the refresh button and if you downloaded it from the store it will be there.