These TCG rulings were issued by Upper Deck Entertainment and have since been deemed unofficial by Konami. They were previously considered official and can still be correct, as long as they follow the official gameplay rules, or unless Konami has issued a ruling that says otherwise. References: 
If "Spatial Collapse" is activated, and an effect is chained so that a player has more than 5 cards on the field after "Spatial Collapse" resolves, the controller selects cards to send to the Graveyard to make the number 5.
You can activate "Spatial Collapse" when you have 5 or less cards on the field and your opponent has 5 or less cards on the field.
"Spatial Collapse" includes Tokens, too.
While "Spatial Collapse" is active and you have 1 or more cards already on your side of the field, you cannot activate "Scapegoat" because you would have your 1 previous card + the "Scapegoat" card + 4 monster tokens = 6.
When you have 4 cards on your side of the field while "Spatial Collapse" is active, you cannot activate "Change of Heart".
When "Cyber Jar" is activated while "Spatial Collapse" is active, if the number of cards exceeds 5, each player selects cards to send to the Graveyard to make the number 5.
When you have 4 cards on the field and you activate "Remove Brainwashing", you select cards to destroy to make the number of cards you control 5.