Problem:

When you use the red X and remove an item (Data Item, Statement, etc) from the Revolve Enterprise Edition Worksheet, how can the deleted item be viewed and/or restored?

Resolution:

Restore via a filter.

The easiest way is to right-click on the Type column header of the WorkSheet (by default it is the leftmost column), then choose Define Filter.  This should bring up the filter dialog on the Candidates tab.  Choose either of the filter options other than not filtered.  Now the removed items can be viewed.  If select item/s and click Red-X a removed item will become a candidate again.