This is a custom version of the Display Level Message sprite (sprite 19 in vanilla SMW). This one uses the extra bytes to determine which message to show. A version for RPG Hacker's VWF message patch is also included.
I made made a couple tweaks in the ASM file (e.g. added SA-1 support and made it so that the message number is stored after the check when a message is active). I also set the first extra property byte for the VWF file to one (it used to be zero).