Your leak sounds just like mine. It's a slow leak coming from either the water pump or the 'O' ring behind the engine.
I am going to do the timing belt and water pump maintenance this spring, and I hope it fixes the leak. If it doesn't, I will assume it is the 'O' ring. It is my understanding that the 'O' ring fix is difficult because the head has to be pulled and gasket replaced.
This leak is a slow seap that pools on top of the engine. If the VX sits, the coolant pools and dumps down onto the floor of your garage. You won't notice the leak as much when you are driving regularly because it drips down and blows off the bottom of your VX. I have had this leak for 2+ years. Keep your coolant overflow reservoir full and wipe up the mess when you see it until you have the time/money to get it fixed.
Bart