When mapping commands to keys in modal mode, modifiers can be specified for the enter-modal-mode key but not for the actual key. I would suggest adding that option.

Suppose I have the following key bindings:

bind up:f9;cmd push up
bind up:cmd;f9 push up

Currently, these two are equivalent and will be activated when one enters modal mode using cmd+f9 and then presses the upwards arrow.

I think the desired behaviour would be if the first syntax did exactly that while the second syntax would be triggered by entering modal mode using simply f9 and then pressing cmd+up.