can't get 4 options to show

I am trying to add four different optional items to our first test item for sale but can only get it to add three

see:

master.shopcen.co/index.php/products/pro...0mm-high-performance

I don't know why this is happening as the fourth item has been treated the same as the other three

it just won't show... no errors or anything

pic 1 shows all 4 optional items on the back end

pic 2 shows what is displayed on the front end

all items are published and display on their own

show out of stock is turned on - all products have nil qty

this is the product listing here

master.shopcen.co/index.php/products/pro...-550x700mm-skylights

I found what it was....

somehow I had inadvertently clicked on the 'date available' calendar when adding the product, and had it set for a date in the future so it was notdisplaying as able to be sold