The BIOS .zip file contains only the BIOS, nothing else. Everything else you mentioned (except AXTM BIOS) are drivers that you install with your operating system (OS), Windows, and are both on the disk that came with your board, or can be downloaded from your boards page at ASR's web site. You must unzip that BIOS file yourself before using it. On another PC, try right clicking on the file, and if you see Extract in the list, that will unzip the file.
The BIOS is stored on it's own CMOS chip, and is separate from the OS. The latest BIOS version will have all previous updates in it. I don't know what the AXTM BIOS is. If it's a beta or experimental BIOS, don't use it!
You did not mention all the driver and other files you need to load once Windows is installed. They are on the disk that came with the board, or can be downloaded from your boards page. Yes, you need to install all the things you mentioned, and more. Running the automatic installer on the disk will install everything you need, and likely a few things you don't, but you can remove them later.
You might be able to update the BIOS with the USB drive without an OS. Plug a USB drive into the rear I/O panel, and get into the BIOS and see if it is recognized. If not, check the manual about BIOS updates (read that anyway!!) for more information. Download the manual from your boards page, if they don't give you a hard copy.