Is there a way to remap the input buttons for the pre loaded games?

Is there a way to remap the input buttons for the pre loaded games?

I am trying to set up my new Z2 for Rainbow Six Siege and a frustrating thing I am running into is reconfiguring little things like primary gadget and sprint to where I like them to be. The issue stems from when I remap these things, instead of remapping an input labeled mouse button 5, it reads the inputs for Siege originally set as the actual input button. Meaning the mouse automatically makes the finger button select weapon 2, which then programs the input for that button to be Key 2. So if I try to switch it, I essentially lose the functionality of two keys/inputs. Is there a way for me to have the inputs of the mouse not be assigned to existing input options assigned by the game? (i.e. create mouse buttons 4-8 and have them separate 2, shift, caps lock, and others.)