I haven't used 202 hack myself, I just use a little MIDI to CV convertor to play my 202 although its not great as I need to get the 202 modified to get rid of the latency (the input pitch goes through the sequencer first - this also means you loose the ability to do pitch bends from a control keyboard if not modified).

The numbers represent the length of the notes - theres little pictures of the note type under some of the keys - if you press one of them in step mode then it puts up the number. I think a quater note works out as 48 or something. Use the dot (.) key to get a length + 1/2. I think the gate times tend to default to 1/2 the note length when editing it.