This is the default checkpoint brick one:
function brickCheckpointData::onPlayerTouch(%data, %obj, %player)
{
%client = %player.client;
if(!isObject(%client))
return;
if(%client.checkPointBrick != %obj)
{
%client.checkPointBrick = %obj;
%client.checkPointBrickPos = %obj.getPosition();
commandToClient(%client, 'BottomPrint', "\c4Checkpoint reached! \c7- Say /clearCheckpoint to go back to the beginning", 3);
Parent::onPlayerTouch(%data, %obj, %player);
}
}
Fixing it to be only for the brick owner depends on how the salvage mod places bricks. (Do they go in your brickgroup or the one the brick came from? Does it set brick.client which'd only work until you leave?)