Hi i have been searching in the forums for help in these two things but i couldnt find any help, so, lets see if you can help me

1)How can i make a big explosion decal? i have changed the line in the decal.fpi size=x but it doesnt work even with commands of 200 or 300, and i had made the decal picture bigger, but, its still small
2)Anydoby has a script to make a explosion decal show for 3 seconds, play a sound and dissapear when the player is in a triggerzone? I had seen a tread to make an explosion but the script seems like it doesnt work
3)Does somebody know a way i can make a smoke decal display when i shoot a wall? like it happends when i shoot the floor
Sorry for this n00b questions, but i hadnt found an answer

Thank you