Since you ask on the 3rd issue, I assume you have successfully completed the 1st (importing the WSDL) and the 2nd (using the randomNo.soap service created by the import).
Anyway, regarding the change to stage 3 of the Twitter demo, you should keep of course #1 (creating List) and #2 (adding the Content Item element), but then you should replace the Get Top Trends service by your own service. Your service should call the web service and then create from each result and item to display (i.e. model your own Convert to Content Item).
By the way, from what I see, the response of the service (randomNoResult) contains only a single number (minOccurs="1" maxOccurs="1"), so the list you will display in the iPhone will contain only a single item (the random number itself?).
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