Terry,
To be able to remove an individual item from a reference list, add operation Delete of type 'Delete form list' in the 'Operations with item' section in the bottom left corner of the attribute dialog for attribute Account.Prospects (I think operations Edit and Delete are added there by default when you create a reference attribute in the first place). In the operation mode, each individual item in the Prospects table will have Delete hyperlink on the right. Clicking the hyperlink will disassociate that particular prospect from the account and consequently remove the item from the Prospects table.
If you want to be able to delete all items from the table in one go, tick 'Generate Delete All button' in the attribute dialog for attribute Account.Prospects.
