If you have a blade and don't know if it's positive or negative hook, sight, or lay on a ruler from the bore hole to across the face of a tooth. If the face is in line with the hole, it's zero, If it leans forward, it's positive, if it leans back it's negative. Miter saws and RAS's work best with negative.
As for tipping the saw back, I suggest that's not a good idea. I've always had them level, which means the base, and the table. If you are concerned with having the motor retract, be careful on how you accomplish it. You don't want anything overpowering the movement or that produces a sudden course of action. There are retractable mechanisms on the market that (recoil) the motor, but it's a gentle return, and has a very slight resistance when pulling. It's called a cutterhead return
. If you are operating the saw over a period of time, hanging weights off a cable, pulley and weights, it can get tiring.
IMO, a bungee cord would be too much of a reaction to be a safe method. If you use a cord, or facsimile, and a small weight, using a double pulley on the wall and a single pulley on the motor, would make the instantaneous response more gradual. Run the cable from a fixed point (where the pulley is mounted on the cutterhead), back to the wall, through one side of the pulley. Then run it back through the single pulley on the cutterhead. Then back through the second pulley on the wall and feed down the wall with a small weight. Allow enough space for the weight to move freely.
I wouldn't lock the arm each time. No real need to do that if the saw is level. Without any recoil device, a level saw should remain right where you leave it on the track. So, returning the motor to the rear should be sufficient.
What to check for regular maintenance? Well, IMO, the RAS is one of the most complex machines you will likely have in your shop. It has raising and lowering capabilities, different parts rotate, roll, pivot, and bevel. There are different restraining devices, such as cammed levers, knobs, bolts, etc. There are plenty of parts to check for wear, movement or movement when tightened. Rolling parts that can be checked for smoothness, and lateral deviation.
Check the cutterhead for side to side play. Check the angle of bevel if it stays true. Check for a parallel blade travel to the table top. Many things to check with all the fittings, and movable connections.