It's like
/remap jump gp1b1
for gamepad 1, button 1 (1-4 are front buttons, 5-8 are triggers/bumpers, 9-10 are Start/Select)
or
/remap left -gp1x
/remap right gp1x
for X axis (either analog or dpad)
Sorry for the mess - Spelunky SD is (I think) my 3rd most popular mod, but also the one that utterly failed to attract any support for my months of work (grand total of $11 in donations), so, to save time, the newer features are mostly mashed up from parts of other mods or personal projects, and these don't always work with each other, so they get swapped out for something else that still works whenever I need to update a big chunk of it.