Need help w/ Custom Picker within a custom field. No matter what I try, SharePoint 2010 saves the entities as the string System.Collections.ArrayList instead of the ResolvedEntities.Keys. What am I doing wrong?

Here's a link to two solutions – one contains the custom picker, the other contains a custom field that implements the picker.

https://www.onlinefilefolder.com/3sl2JjKLGHSasQ

Thanks,
Joshua