wierd rom size!!

[podge]

can anyone help ihave written roms to my flashcard with no problems but i have found that some of my roms only show a file size of 0.50 mbits when i try to flash them to the cart and they will not run do i need to patch them or am i doing something wrong the roms i have found this problem on are goldensun 1+2 and also balders gate dark alliance any help will be greatly appreciated.