Afraid I can't be of any help with the splashes as I still battle them myself '-)...although now that I think of it, maybe wabe will join in with "his" technique of mapping vegetation with water .mats to create splashes?

However, for the footprints, assuming you have Poser?, you can use a boolean on the shoes/feet and the terrain as I did in this image...
http://www.renderosity.com/viewed.ez?galleryid=1023243&Start=1&Artist=spider1313&ByArtist=Yes

This, of course, will take a bit of playing around to get what you're looking for, but it may be worth a try?