Thank you Captain Sim.  I appreciate very much the support that I received on this problem from CS.  
I know that there are so many add-on utilities and computer configurations that it would be impossible for CS to assure compatibility for every outside program that is going to be running next to your software.
Yet you showed patience and went the extra mile with me.  As a long time CS customer, I deeply appreciate that.
I will be looking forward to the release of the 727-200.  

For anyone else interested, a side from the cut-off fuel switch problem and having to start the two engines using Ctrl+E,  the registered version of FSUIPC seems to work well with the CS727 in all other areas.
If I run into any more problems with it, I will post them here.
I find the main advantage of using registered FSUIPC with the CS727 is if you are using a throttle quadrant, you can easily activate the thrust reversers upon landing with the throttle levers instead of hitting the F2 key several times.
I guess one just has to decide whether you want realistic startup or realistic landing  ;)