First make a backup copy of the file "Available_Boards.txt", which is located in your Supreme/Saved_Data folder. Then open up the original with any text editor and make the following changes:

{
"Board_1",1,
"Board_2",1,
"Board_3",1,
"Board_4",1,
"Board_5",1,
"Board_8",1,
"Board_10",1,
"Board_11",1,
"Board_12",1,
"Board_13",1
}