1. If your motor is being rebuilt at this time, it would be a good idea to tell the shop about the white smoke so they can take a closer look at the head and water jackets near the cylinder walls. If you don't tell them about it they may overlook it and it may not be fixed.
2. Yes, transmission fluid can get into the combustion chamber on automatic transmission cars. You have a vacuum line going from the vacuum modulator on the trans to a vaccum port, which in turn goes into the engine. So yes, it is possible to burn tanny fluid.
3. If you have a head gasket leaking into a coolant port, your coolant would boil over. One way to identify the source of a coolant/combustion chamber leak would be to pop the radiator cap when the motor is cool and start the motor. If the head gasket is leaking at a water port into the cylinder, the coolant will litterally "burp" out of the radiator each time that cylinder hits the compression stroke. (I had a Humvee do this to me once) By the way if you try this, please wear safety glasses.
4. If your head gasket is leaking oil there are three simple ways to determine where that oil is goin. A. Compression test. B. Check your radiator. C. Check you oil. The manual that comes with your compression testor with tell you what readings to look for if you suspect a bad head gasket. Now, you may wonder why I said check your radiator and oil. Many times if a head gasket goes bad, it will allow oil to mix with coolant or vise versa. If your oil or coolant look milky, I would suspect a head gasket or cracked head/cylinder.
The mapple syrup smell is coolant being burnt. If you smell mapple syrup in the engine compartment, you may have an external coolant leak. (hose with a pin hole, loose hose clamp, or even a leaking water pump or thermostat housing) I would use a cooling system tester and look for drips/some times steady streams of coolant and puddles on the ground. Since your motor is being rebuilt, this is kind of after the fact.
I hope this helps a little.
Ted
