Thanks for contacting us! I agree, having the ability to preview how the posts will turn up would be incredibly useful! I will gladly pass that feedback along to the appropriate teams for review. As to uploading art, you should be able to select images from your library and upload new images during the scheduling phase of Social Share by clicking on that thumbnail just to the right of the text box of the post. As for any platforms not listed in Social Share, you would need to use the email URL and post it manually.
Glad to hear you are having a great time, let us know if there is anything else we can do!
Briody_W Community & Social Media Support
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