No, a robot may only use a maximum of 1 Barrel and 1 Ball as Preloads, as per <SG2> which you quoted above.
No, the only contact with robots permitted during the Driver Controlled Period is for robots which have never left the Alliance Starting Tile, for the fixing of robots which are unable to move. This is spelled out in <SG6> which you quoted above.
No, <SG6> specifically applies to robots which never left the Alliance Starting Tile.
No, this would be considered both unsafe and a risk of damaging the field, thus a violation of <S1>, which is quoted below.