RNBO: how to process relative MIDI CC messages

in Max for this I first did [sel 127 1], so I get bangs for decrement 1 and increment 1
then after those 'dec' and 'inc' messages into an [incdec] object cross-connected to a dial

there's no [incdec] in RNBO though, so perhaps feed an [accum] with '-1' and '1' messages would be cleanest
but how can I reset this [accum] to a specific value other than 0 though? I can't seem to get it to work even after playing with (and being kinda confused by) the @hot and @resetmode attributes

maybe I need to resort to doing this in a codebox? seems like there should be a simpler and cleaner method...