Hello, is there any way to program the register be able to take inputs while the till is open? If the till is open any button pressed yields an error noise and symbol and I would like to be able to use is while the drawer is open. Thanks for the help!

There is a way to do this. You need to change one of the service lines. Now, assuming no-one has done any changes in SRV mode since you got the machine, you can change service lines in PGM mode.
To run with open drawer go to PGM, type in 9913 . @/FOR 0100 CA/AT
That makes it 'Drawer Closed Non-Compulsory'.