Just a heads-up, there's an issue with playing the Splat Pack in the Windows version. (Not just the GOG release, it was in the original as well.) It seems that for some reason that apparently nobody has been able to determine, the Bugutti and the Sled may crash the game.

Again, this is just in the Windows version. They won't crash the DOS version. However, If you (like me) can't get the DOS version to run well enough and must play the Windows version, there's three ways around this:

1. The easy way: Avoid them

Before you start a race in the Splat Pack, hit the "View Info" button, and then "View Racers". If you see Lady Bug (driver of the Bugutti) or Sinthea (the Sled) in the lineup, hit "Change Race" and choose a different one. The opponents will be randomized every time you switch, even if you switch back to one you checked before. Just keep switching until neither Bug or Sinthea is in the race.

Also, if you somehow acquire the Bugutti or Sled to drive yourself, don't try to drive them. This will also crash the game.

2. The not-quite-as-easy way: Fix them, maybe?

This seems to fix the issue, but I've read somewhere that it's not guaranteed.

First, you'll need to de-encrypt the game's files. Go to the pre-race menu (the one with "Change Race", "View Info", etc.) then type IWANTTOFIDDLE. You should hear a tire squeal, the game will freeze for a moment, then another squeal. Voila, de-encrypted. The game will still run whether the files are encrypted or not, but if you want to re-encrypt them, just use IWANTTOFIDDLE again.

Quit the game. Open your file browser, and go to the directory you installed the game to. Open the CARSPLAT folder, then the DATA folder, then CARS.

Make backup copies of BUGGIT.TXT and SLED.TXT. Open one of them (the original, that is, not the backup).

Find a line that says:
11,-1,2,1 // Driven wheels GroovyFunkRefs (for spinning) - MUST BE 4 ITEMS

Change that 11 to a -1, and save. Do this for both.

Run the game and see if it worked! As I said, I read somewhere that it might not work but it seems to for me.

3. The also-not-quite-as-easy-but-ultimately-time-saving way: Remove them from the game entirely

As with option 2, you'll need to de-encrypt the game's files. Follow the instructions as above.

Go to your CARSPLAT/DATA folder, as before, but don't go into any further subfolders. Make a backup copy of OPPONENT.TXT just in case, then open the original.

The very first line will be the number 40; This is the number of racers in the game. We're removing two of them, so change this number to 38.

Now, find the data for Sinthea (Opponent 2). Delete every line between the lines that say "// Opponent 2" and "// Opponent 3". The two slashes means that these opponent number lines are commented out; The game doesn't pay attention to them, they're strictly there for human convenience. You can delete one of them if you want to keep things tidy, but it isn't strictly necessary.

Scroll way down to Lady Bug's data (Opponent 21) and delete it as well. Save. You just got rid of the game-crashing opponents! Well done, have a cookie.

I haven't tested the game extensively with these two opponents removed, but if it's done properly then I can't think of any reason why it should create any problems. If there are, well, that's why we backed up OPPONENT.TXT.