Can't recommend this course enough. Martin Odersky is a great lecturer and very passionate about functional programming. Learning Scala was a useful bonus too.
On the other hand, I don't know if you use Javascript much, but you'll see it in a very different (much better) light after taking a FP course.
Most likely the GP is complaining about the fact that the server-side tests were on bigger datasets than the ones that shipped with the code; but that wasn't a big issue as you could keep resubmitting up to the deadline.
I found it useful to remember that almost all of the solution functions were very short; most were one line, some up to five; if you were writing long functions you're most likely doing it wrong. Similarly, the local tests should finish almost instantaneously. If they take 30s with the local dataset, they'll time out with the larger dataset on the server.
I went through all the homework and passed the course with the maximum grade. Except for the last homework where I too was guilty of the above, all submissions took the maximum grade from the first try. I don't remember encountering any confusing problem definition and even if a problem is confusing to you, there were plenty of people available on the forum and all you had to do was to ask for clarifications.
Also, in regards to solutions, there were really helpful advices in the assignments' source-code. Sometimes all you had to do was to translate English to Scala.
However, he tends to talk slooooowly and methodically (him being German/Swiss is probably related), which makes watching his videos kind of unfun, and there are no slides.
There's an hour of lectures, and I'm pretty sure I could say the same stuff in a 10 minute video at most.
I mean, this kind of way of teaching is really ancient and outdated; why would you subject yourself to 7 weeks of watching boring videos, when you could just read his whole book RIGHT NOW in 1-2 days, and then read other books, tutorials on websites, etc.?
Generally, I learn better from books than from lectures, but I found that some of the lecturers in online courses are truly outstanding (Prof Agarwal in Circuits and Electronics at MITx, Profs Ng (Stanford, Machine Learning), Egerstedt (Georgia Tech, Control of Mobile Robots), Pattison (Berklee, Songwriting)), so listening to their lectures was worth it. I did not quite find Odersky as strong as a lecturer.
`mplayer -af scaletempo` and then pressing ] to increase the speed of the video, without altering the pitch of the sound, was my solution. (And I hear also the Coursera player lets you to change the video speed.)