VB.NET app for route management

Build us a VB.NET software module/component as an engine to determine various routes possibilities between a currently selected pair of source & destination. Our software application involves dealing with multiple tanks storing some liquid chemicals that need to be transported via pipelines & valves to another tank(s) & some other locations. The valves layout is complex & each valve leads to multiple options on destination side & receives from multiple source lines. The valves are 2-state - either closed or open. We shall always 'know' their current state. Also, each valve will have 'available' boolean status - saying it is good to use it in a potential route. The engine will support any valve & pipeline combinations that may be changed by a user, preferably via the database entries. We only need a generic software engine module built that eventually will be integrated into our larger project that is already built using VB.NET & SQL Server latest editions. Short-listed candidates will be provided with a sampling of the valve & pipe lay-out. The engine will identify all possible routes between selected source & destination 'visually' on a VB form. It will also show the 'in-use' routes. The solution shall also outline suggested options based on the fact that minimum quantity of valves employed in route and or the minimum no of valves 'to be moved' to use the route(s), while a user is committing a source to destination transfer. The solution should be preferably designed using MS VB.NET & MS SQL Server. If you feel another solution is a better mousetrap, provide reasons (there should be no proprietary content) else we shall assume you comply with our preference. You will provide full source code & release ownership of the proposed solution to us. Daily source code submission is required to show the work progress. The solution will entail 2 phases - 1. Build & deliver engine. 2. help us integrate into our VB project (allocate 8 man-hours). Bid only after fully reading & understanding, ask questions otherwise. We like to get phase 1 completed in a week after award. The fixed price budget is negotiable around US$350.