In general, I like how Skritter asks you to write both characters of a new word even if you already "know" one of them very well. Since Skritter provides you with pinyin sans tones, you need to pick the correct character in your mind and then know how to write it.

The weird behavior comes when you encounter a new word, say "shi shang", that you haven't encountered before. You (by "you" I, of course, mean "me") aren't sure which "shi" is correct, so you try a few (事，實）, and before you know it, 時 pops up with the angry red border!

I think that if it is your first time seeing a compound, any mistake should count as a blue bordered error (along with any bookkeeping that happens in the background), rather than the embarrassing red error. Your error is associated with the new word, not with the old character.

Also, does anyone else ever have Skritter interpret a 4th tone line as neutral instead? Maybe it's just me.

I just realized my griping is obsoleted by the grading buttons in the new practice mode.

that and I remember something about them doing away with the blue border in favor of just green=learned and red=everything else. Not sure if that has happened yet on the new interface or not.

Are you talking about drawing the 4th tone? I occasionally get neutral instead of pretty much all of them, and most of the time i catch it and click the right one so I don't get marked wrong. Using the keyboard to hit 1-4 with your left hand is definitely a surer and usually faster method, though.

nowadays, you can push 1-4 for different levels of 'knowing'. I can't remember which number correlates, but red = don't know, yellow = so-so, green = know, and blue = too easy.

I know the problem you're talking about, and my suggestion is to either leave it as red - you may know the character, but you do have to learn that that character fits into this particular compound - or just change it to green, 'I do actually know this'.

Old:
Blue = don't know
Red = forgot
Green = know it

New:
Red = don't know / forgot
Yellow = so-so
Green = know it
Blue = too easy

We tried having a lighter shade of red for "don't know", but the only two people we showed it to thought it was confusing. We could try that again, though. Red is awfully angry, it's true.

I do still have to make the grading smarter about getting component characters in new multi-char words wrong.

Neutral tone recognition is whack. I gotta fix it. I recently added a special case where a long-enough stroke can't count as a neutral tone, but maybe it's still too loose; I'll decrease the length threshold on that a bit.