Placing other activities in a For Each Document activity, as well as nesting For Each Document activities is not allowed.Activities placed in the container will process one transaction document at a time.In the usual Process skill workflow, a single collection of documents exists for each transaction. Inside the For Each Document activity in the example above, this collection is split into a number of collections equal to the number of documents in the transaction. Each of these collections contains only one document. The For Each Document activity will process the collections one by one. Hence, each transaction document will be processed by the condition script individually and will then be processed either by the Extract activity or by the Custom activity.