The different colored rays emitting from Mary's fingers are the gems as described in the Miraculous Medal apparition, and Mary, in saying Fiat, would have all the gems, and thus be Full of Grace.
The Fiat from Mary made it possible for a woman, brought into existence at a place in time, to bring forth the Eternal. And bringing forth the Eternal, she brought forth all that God is. Therefore, there is nothing that we attain in blessing from God that does not come through Jesus' Mother, Mary, even if we don't specifically ask her or even know to do so. She was the Chosen Vessel to bring forth the Man God, and the Man God came both as Man and God, the Second Person of the Holy Trinity, the Almighty and the Eternal, consubstantial with the Father and the Holy Spirit.
Mary is wearing a blue veil and dress and red shawl, which colors signify that she is both Virgin (red) and Mother (blue) simultaneously.
All that God is is symbolized by the Old and New Testaments here. The Decalog symbolizes the Old Testament, the Law and the Prophets, which obtained their fulfillment in Jesus Christ. Jesus Crucified with arms outstretched in the same gesture as Mary's -- symbolizes trust in the Eternal regardless of whether the event is Joyful, Luminous, Sorrowful or Glorious. Jesus' side is emitting the Water and the Blood, the Divine Mercy, for which He came into the world as man and died to give us in the Redemption. Jesus Crucified symbolizes the New Testament in its fulfillment of the Old Testament, including the Evangelization through the four Gospel authors, Mark, Luke, John, and Matthew.
These are all things coming through Mary, coming from God and being God, therefore they are shown entering and going through the Eucharist in the Monstrance, which Monstrance is made of a Rosary. The Rosary symbolizes the lives of both Jesus and Mary, the perfect examples, and is used to meditate upon these to obtain the graces to make us all integrated persons and happy children of God.
The stem of the Monstrance shows Mary's Sorrowful Heart with the Seven Swords symbolizing the Seven Sorrows of Mary: The Prophecy of Simeon, The Flight into Egypt, The Loss of Jesus in Jerusalem before finding Him in the Temple, The Meeting with Jesus as He Carried the Cross to Calvary to die on it, The Crucifixion of Jesus, The Deposition of Christ's Body from the Cross, and The Interment of Jesus.
The base of the Monstrance is again the Rosary in the Rock, the Cave of the Resurrection. Christ is seen in the act of resurrecting, symbolizing that Christ is the Resurrection and the Life, as He is known in the New Testament, and the Great I AM of the Old Testament.
I drew this logo myself for the Society of Mary, Mother of the Eucharist, during October 2009, the month of the Holy Rosary, finishing the majority of the work at St. Mary, Mother of God Church in Chinatown in DC, on October 11, 2009, the Patronal Feast of Mary, Mother of God Catholic Church.