1) just to assure you, the batch converter does work, otherwise we would have been flooded with emails about it which we haven't. please try changing the output folder to something different than the input folder. what effects did you add to it?
2) the step increments for the left and right arrows are not course they are very reasonable, making it any smaller would result in issues with sampling inaccuracies (i..e. the file would not play at exactly where you selected). this is a generic audio issue and not a wavepad issue.
3) the scrubber does exactly what you think its supposed to do, it is playing the audio at the selected point in time.