All is fine if I follow the airwire routing from one pin to the next,
    but I want to change the sequence of the connections to better connect
    decoupling capacitors. Is there a way of doing this ?

You don't HAVE to "follow the airwires" - when using the route
command/button, you can start at any airwire location, and route to any
point on the same network (click twice to terminate the route.)  Then you
can use the rats-nest button to recompure new airwires, and it will notice
that there's one less...  (actually, you don't even have to route to the
same network - you can stop in the middle of nowhere, which is occasionally
useful because the new endpoint (and verticies) become possible endpoints
for new "shortest airwires.")

Does that help?

BillW

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.