This page is a complete mess, and I have no clue when I'll clean it up. :)

Here's a quick and dirty explanation of this tool. BMPSplitter has two functions: exporting animations and tile maps.

Animation/Sprite Export
To export an animation, either use bms files or hit 'Add Frames'(ctrl-f) on a new document, then select multiple frames, I suggest hitting ctrl-a in the folder you want. The order they're selected matters(I'm not sorting) and it won't group anims if their not sequential. Animated gifs will export as if they are a series of frames, so they make for good storage for animations. Then hit 'Export', most of the boxes should fill with defaults.
The 'PaletteOffset' number will shift the pixel indices in your tiles by that number, with the exception of the transparent color(which the tool will assume is the color in the top left corner of your first image).
The '1DBlockSize' parameter of the bms file will force the export to pad frames to the block size you have selected, so if you set the block size to 128, sprite smaller than 16x16 will be padded to 16x16, and with 1dblocksize set to 256, all sprites will be at least 32x32. I haven't added this parameter to the interface, so if you have a bigger block size I suggest you create a bms file for each anim/sprite and just load/auto-export those.

Tilemap/Bitmap Export
To export map tiles, hit 'Load Map'(ctrl-m) on a new document, select a bitmap that you designed to be broken into 8x8 chunks, the tool will then look for identical tiles and optimize the map, it currently doesn't check for horizontal/vertical flipped tiles that are the same. Then hit 'Export'. Selecting 8bit or 15bit linear will not optimize it into 8x8 chunks, it will just export a bitmap.

Downloads
Here's a link to the file:
BMP Splitter v2

I'm not sure if these sample files will work with v2 of the tools, but I did include a sample bms file with in the bmpsplitter zip as a reference. Regardless, here's a link to some sample art, it's the archer and my world map tiles from 'A Touch of War'. If you want to try autoexporting the archer, you'll need to edit the bms file by hand, since it contains full paths, not local ones.
Sample art

A couple of bug notes:
Save doesn't do anything but create a zero byte file, so don't use it.
I've run across some cases a while back when dmacopy's of the exported arrays don't work right, I think it has to do with memory alignment, but I haven't seen it recently, so I didn't look into it.