Hi Adrian,
The zipped shapefile is 1.3 MB. It is a .zip file. It is a polygon file, wit the polygons being zipcodes, so the problem might be that there are some multi-part fields in the data.
I added the zipped shapefile as an item in ArcGIS Online with no problems. I then went back to Community Analyst and added the feature service using the Custom Data Setup method. That worked, so the immediate problem is solved. Thanks you for your help - that article is now in my list of bookmarks.
The point behind this exercise is that I am working with public health students who have limited GIS skills but want to include some GIS analysis in their work. I'm trying to document as simple a set of steps at possible so the students can be somewhat self-sufficient at this task. The students are designing health-based intervention programs, and part of their design is to select locations for the mythical intervention offices near the target populations. For several semesters I have been teaching students how to use Smart Map Search to select data variables relevant to their health condition of interest and then use the sliders to isolate the census tracts most likely to have greater proportions of their target population. One problem we have encountered is that Community/Business Analyst does not have a lot of health condition/ailment data. Our university recently licensed Simply Analytics, which has more of this data, so we are exporting shapefiles to then import into CAO/BAO to hopefully use in Smart Map Search. Sometimes it's working, sometimes not - but it's a marked improvement over where we were previously.
Thanks for the help!