What does it mean to say that the Kingdom of God is "right now, but not yet"?

To say that the Kingdom of God is "right now, but not yet" means that Jesus always gave all of himself to God. By "selling all that we have", but not literally, we can fully find ourselves in the presence of God's reign.

What kind of evil is not caused by sin?

The kind of evil is not caused by sin is the kind of evil that often challenges Christians' basic conviction about the goodness of God. This kind of evil is expressed in the suffering, pain, and often untimely deaths brought about by natural destruction :(such as hurricanes and earthquakes) and also by sickness and diseases such as cancer.

In what sense are sin and evil different realities?

Sin and evil, in realities, are different in the sense that sin is not freely chosen, rather, an act that is regarded as a transgression of God's will. Sin, however, is that which causes harm, destruction or misfortune to all God's creation.

What exactly is personal sin and communal sin?

Personal sin - Freely chosen actions that have negative effects on the sinners as individuals and on their relationships with other people.

and

Communal sin - Affects all people simply because we live in a community with one another.

Examples: Poverty, war, destruction of the environment.

When will, or does, Jesus' dream of the Kingdom of God become realized?

Jesus' dream of the Kingdom of God become realized when someone figures out the Kingdom of God as a state of being, not as a place on the earth. It is brought upon people's actions and feelings through Christ. The Kingdom of God cannot be fully established until all people think, act, and feel this way.