Jamal,
That is a problem with the sample data. A wNetworkStructure feature in the sample data is not properly connected. The new release of the data and tools(release just now) has this fixed. You can download the new version with the updated data or find a structure in your dataset and connect it to your network.
http://www.arcgis.com/home/item.html?id=14bdfb26bc2f4e0388a633fbd0ccca02
1: Because water is a pressurized system, this tool finds all valves that lead to a water source and returns them. Just closing one valve is not going to stop flow to the break location. The tools does look at flow, just if a valve is feed water by a source. If you do not want to trace to a source, set the source as non operable.
2: The tools are AddIns in ArcMap, you remove them using the Add In Manager, not windows.
3: You do not have to modify the code for the tools to work on your data. You just need to update the config file. The last tool on the infrastructure reporting toolbar will open the config file for you.
4: To set flow on your water datasets, you need to define the source of flow, but even this will give you indeterminate flow(circles). You need to use the Set Flow based on Digitized direction on the Infrastructure editing toolbar. But as I explained early, this will not accurately show flow because of being pressurized.
1: Yes, make those changes. The Operable fields is a Yes No field telling the tool to use that asset or skip over it, say a valve is stuck open, you set it Operable = False or No, and it will be skipped. Create an Operable field that is a short int and apply the Yes/No Domain and set them all to Yes.
2: Sorry, had a typo, the tool does NOT look at flow. From each valve, it does a trace to find connected water sources.
3: No, just enhance and make things easier.
1. Make sure that valve is connected to the geometric network. Start editing, select it and move it, does the network move with it. Also is the valve operable?
2: Remove fittings
<add key="TraceIsolation_Valve_FeatureLayer" value="Valves" />
3: Add a field to your valve layer and your source layer called Operable. Apply the dmBooleanYesNo No(0)/Yes(1) domain to those fields and calculate all your sources and valves as operable.
<add key="TraceIsolation_Operable_Field_Valves" value="Operable" />
<add key="TraceIsolation_Operable_Field_Sources" value="Operable" />
<add key="TraceIsolation_Operable_Values" value="0|1" />
<add key="TraceIsolation_Valve_AddSQL" value="" />
The issues is a data issue. If you scroll to the right, you will see that the water main is Capped. This means no water is entering the main, means no pressure, means no reason to turn the valve since no pressure is coming is coming from that side. The tools checks each valve and makes sure it is feed by a source(it will not trace through other valves returned by the trace).