Hi,
The javascript getPaymentMethod in this module clobbers the stored credit card functionality provided by uc_cim, because the HTML replacement in the callback ends up wiping out the radio options in uc_cim's subpane instead of updating the actual payment_methods pane.
Took a while to figure out where we were getting this problem! It turns out we aren't actually using uc_conditional_payment, so I haven't put together a patch--disabling the module solved our problem...