A few questions about this particular game:

Is there a list of acceptable words? It'd be nice to know which odd 2 and 3 letter words aren't recognized so as not to weedle the time down.

Does every board offer the possibility to score more than 400 points or should you continue to play boards until you get the "lucky one" that really does offer you lots of words? Or simply, are some boards just duds and I am not as dumb as they make me feel?

It seems to me, by accident, that you can spell a word by scrolling backwards through the word to a vital letter? Or am I imagining that? I get the criss cross and zig zag possibilities but can you backtrack through a word?

It just takes practice.