Others have given answers already, but here's "the official reply":
Does Steel Beast have a start up sequence (like fuel pumps, hydrualic pumps, etc.) or do you just press a key to start the engine?
Some vehicles do, provided that the scenario designer set a variable in the scenario to NOT have the vehicle battle ready at mission start. Even then however, starting up a tank is usually less complicated than an airplane with multiple engines. The main focus of Steel Beasts is tactical combat. Army customers also want it for crew procedure training, where commander and gunner are the training audience. Steel Beasts is not a driving simulator (a lot of work would be involved there for comparatively little gain, as far as we can see; the same can be said for a loader's position).
Is there a bail button (as in bailing out of the tank)?
Arguably, as long as the tank isn't on fire, the safest place to stay is inside, and once that it actually is on fire, it's usually too late. There is of course a sweet spot in between, and maybe we'll implement such a feature in the future.
Does Steel Beast have smoke generators?
Some vehicles do. Most have smoke grenades.
Do you have to turn a laser on for rangeing or is it always on?
In most vehicles its always on. Some armies wanted to have the laser key simulated as an educational measure so that the crews treat it like a weapon, other armies are more lenient about it. Eventually we'll simulate it in all vehicles where such a key is used, but leave it plugged in and active by default.
Can you control the tank treads individually?
We model the difference of some tanks being able to picot steer while others can't. But by and large all modern tanks rely on some sort of a steering wheel or motorcycle handle bar. Levers to steer tracks individually are a concept of the past. The only vehicle that still does it and which is still in use today that springs to my mind is the M113, and maybe also the T-55 (I have to check that one, though) - arguably the oldest and weakest of their kind.
Do the gears change automatically or manually?
Automatic transmission all the way. Like I wrote above, SB Pro is no driving simulation.
Frankly, I don't understand the interest of many people in the driver's place. While it is a very important position usually given to the most mature crew member after the vehicle commander, from a gaming perspective there isn't much freedom for your own decisions actually. Bring the vehicle from here to over there. Make it as quick as possible, take a concealed route, and try to not get stuck. That's about it.
Do the tanks have variable throttle control or is it just gas and brake?
With a joystick (or steering wheel and gas pedal) you can fine-control the vehicle speed, yes. Still, don't expect wonders. For normal operation Steel Beasts has five speed settings - top speed, medium, slow, stop, and reverse. The practical reality is that as a vehicle commander you don't need more.
Do you have to close (or open for that matter) the hatch after popping out to look around or does it do it automatically.
You may open and close hatches separately, but for the normal user interface if you're buttoned up and you give the command to elevate your point of view, there is a delay and an animation of the hatch and then you go to "chin defilade" automatically. I see very little benefit to convolute the user interface more than absolutely necessary. There is only so much that even with a 3D turret interior one can accomplish wehn all that you have are hotkeys on the keyboard and mouse click and drag options. For example, as a Leopard 2 tank commander to open the hatch you need to turn around and use both hands to
- unlock the hatch
- elevate it to top position
- unlock the swivel limiter
- rotate it
- push it down, and finally
- lock it in place
I can see no value in attempting to replicate that with extensive switchology. That's just occupational therapy to divert the player from the important elements, to maintain situational awareness. Striving for high fidelity incurs intelligent choices about which elements may be simplified and which need to be modeled in full, both in order to support the focus of the simulation. And that is tactical combat, above all. That's complicated enough.