Without more information, its hard to say for sure what the problem is, but its sounds like you may be missing a main image. Without one, the publishing process will alert you to this and will not allow you to continue until you add the image and then save it.
If that's not the problem, can you provide a link to the temporary URL?
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WHAT'S GOING ON?????!?!?!?
http://www.instructables.com/id/edit/?instructableId=EVB5DFLHERLT8FQ#instructableId=EVB5DFLHERLT8FQ,stepId=S20D8GNHERLT8FP
If both images are on one step, then the system will register your project as "too short, possibly spam".
Try re-writing your project as a photo instructable, or spreading out your images and instructions over three or four steps.
If you need to, take more photos (maybe use photoshop to make an attractive introduction photo?).
If that's not the problem, can you provide a link to the temporary URL?