I can't seem to validate a puzzle I'm trying to create. The clues are short enough, and the colors are distinct. The error I'm getting when clicking validate isn't helpful.

The error I get says:
"Puzzle 0/0 FAILED!!"

What does this error mean?

FAILED!! means - it is not solvable. You should see a line (or lines) with circles. The circles mark the problem, tell you where it is, and you need to change those lines or the area around them.
 
0/0 means it is a part of a multi. As a new author it may be hard for you to have the whole image/multi validated.
 
You have two options:
Change the puzzle until to have it solved.
Save the puzzle (multi) and send the .grd file to me ( hagit@griddlers.net ). I will look at it and see how I can help.
 
Regards,
Hagit