1. For the helos you need to look at their JetAIupdate module and compare it with the ones used by, say, a raptor. There are some fields you need to add to it.
2. For the falling bomb speed, for bombs that are fired from a weapon, give them missileAIupdate (replace their AIUpdateinterface with it if they have one, else add it new) and a fast thrust locomotor, see the AuroraBomb for example.
For the un-aimed bombs that just exit the plane via the DeliveryPayloadAiUpdate, like carpet bombs, try increasing their mass to 500 or more, and decreasing or commenting out their air resistance in PhysicsBehavior.
Note that faster may not look better since the planes all fly low, and this is because the camera height is low.
3. Tunnel network uses TunnelContain.
4. The cameo problem is that you are following the EA Games image definition ini files which are all coded wrongly. They start counting from 1,1 instead of 0,0. Use the exact pixel coordinates from paint shop pro or whatever, and you will be fine. Do not follow EA Games who add 1 pixel to all coordinates.
5.1 Check the player template in PlayerTemplate.ini to see if you have enough shortcut button slots for that faction. The max possible in Zero Hour is 11. In Generals it is less.
Also check the specialpower.ini spec to see if it is a shortcut power.
5.2 The missile going sideways is a bug. You can fix it by giving the silo a launch bone which is one of the steam/smoke bones near the missile tip and giving the silo an AIUpdateInterface with a turret that always points 90 degrees up, with FirePitch = 90. Also, change the projectile model to be the same as the Chinese neutronmissile as the American missile is faulty.
See here for a map.ini fix:
Superweapon General Alexander's Missile Silos - Cncmaps Map Editing Forums
As for the cargo planes and the reinf pad, watch the pad when it counts down to 0 and see what happens. I suspect the vehicle may be dropping without parachute, or it drops short or long. Report back what you find out.