Hey I think I figured out a work around for this,
If you have a look at the transposition section in the MIDI control centre you can set a transposition input midi channel. You can then use a cheap midi keyboard to transpose your sequencers on the fly and still have the use of the pads. You'll probably want to turn on transposition latch too... Or not depending on what you want to do!
You can also set up the midi inputs so you can play and record notes into the sequencer via midi. I find both these features super useful!! I have found that sometimes recording notes into the sequencer with an external keyboard requires me to mute the sequencers output, it might just be for overdubbing, but I think there's a bug in there somewhere.
Hope this helps!!