i usually do running reviews where i list all the issues in a game one by one and then the author has a (usually complete) list of all the problems/issues/design flaws. then when the author takes my advice verbatim, their game becomes immensely successful.
but it seems like you did nearly everything right here. just one minor hiccup i noticed so far.
when you step on a checkpoint and hit 'c' it says "saving..." but never gives any feedback to let you know that your progress is saved. this is somewhat awkward and clunky. one is left to assume. but some might assume that it doesn't say "saved" because it didn't properly save due to some browser/flash setting.