Scary pictures - not pretty the damage or the wires... You have my sympathy...
Normally three Red wires connect together. Live IN - Live Out and Live to the Switch.
Normally two Blacks connect together Neutral In and Neutral Out.
The wire that comes back to the ceiling from the switch is usually Black and is NOT a Neutral - it's switched Line (live) that connects to the lamp and turns it on and off. Joins with lamp Brown. Should have a Red or Brown sleeve on it as an identifying warning.
The other side of the lamp (Blue) joins with the two Neutrals to complete the circuit.
I suspect that you have taken the Black Switched Line wire and connected it to the two neutrals (three black wires together). As soon as the switch is set to ON, live and neutral are connected together with no lamp as a load, consequently the breaker trips.
Peccavi
January 2009