Was your data directly inside the zip file? Make sure your files are not inside a sub-folder.
Is your data in a metric coordinate system (CRS)? Make sure you are not using a CRS working with degrees.
Do you have fields in your data with overly long names or special charcters? (e.g. ä, ö). Shapefiles have probelm decoding such data at the moment and this may result in error.
If the problem persists you can contact: opengeohub[at]gmail.com