For those wanting to play around:
The logo.md5 file is just the checksum of the logo.bin file. The MD5 checksum of a file can be calculated using lots of tools. A freeware Windows MD5 checksum program is available from http://www.slavasoft.com/fsum/
(as one example).
As others have said, the V3 (6" EZ Basic) logo.bin is just a concatenation of the two startup and shutdown images, 600x800 each, with four 2-bit (4 shades of gray) pixels packed into each byte. 2*(600*800/4) = 240000 bytes, which is the file length of LOGO.BIN.
As for the V5 (5" EZ PP), I don't know what format they pack the images into, but once that is known, it would be pretty easy to generate a program that would take two BMP files (color, gray-scale, whatever) and convert and concatenate them together into a single file of the right format. Then use the FDSUM program to generate the data for the LOGO.MD5 file.
Only one small, teensy-weensy, itsy-bitsy piece of information that's needed...