What could have gone wrong with my map script?

[xxxxxxxxxxxxxxxx]

You're missing a bracket in void OnStart

////////////////////////////
// Run first time starting map
void OnStart()
{

AddEntityCollideCallback("Player", "TheresNoReturn", "CloseExit", true, 1);
AddEntityCollideCallback("Player", "ChangeMap", "ChangeMap", true, 1);
AddEntityCollideCallback("Player", "MessageFire1", "MessageFire1", true, 1);
AddEntityCollideCallback("Player", "MessageFire1_1", "MessageFire1_1", true, 1);
AddEntityCollideCallback("Player", "MessageFire1_2", "MessageFire1_2", true, 1);
AddEntityCollideCallback("Player", "FireDamage_1", "FireDamage", false, 1);
AddEntityCollideCallback("Player", "FireDamage_2", "FireDamage", false, 1);
AddEntityCollideCallback("Player", "FireDamage_3", "FireDamage", false, 1);
AddEntityCollideCallback("Player", "StartMusic", "Music", true, 1);
}

Edit:

Do you know a quick way to locate it using the notepad++?

Not too familiar with it myself, but if you save your file as for example a .cs file, it will change to a more readable view. (Don't forget to revert back to normal .txt/ .hps later )
In that view, clicking on a bracket will highlight it's corresponding closing bracket and everything that's inside two brackets gets a separate "rollout" to click on.
As for finding missing semicolons, I haven't found out anything there yet...