For some reason VaultWiki had your global max upload size set as 0. This is usually a fixed limit determined by your server hardware, but it should generally be relatively high. I fixed this for you, so please let me know if you still have problems.
Some of your individual filetypes were set kinda low as well, which may continue to give you problems. I believe the inputs are for units in bytes (b), so if you want to accept MB, you need to set it to at least 1048576.