You can access this dialog either through Setup menu item or by left-clicking on the info panel.
Here you can change High Voltage, Cs, Cc, Energy Spread and Convergence for the currently selected microscope. Note: these edits are not saved on exit.
The "Up To" item allows you to change the scale of the horizontal axis (maximum spatial frequency in nm-1) of the 1D CTF plot.
Tip: if you are familiar wit the Windows Registry you can edit the provided sc.reg file (make a backup first!) and then update the registry by double-clicking on the edited sc.reg. In this way you can edit any parameter for a certain microscope or add a microscope.