Shift key as conditional modifier key

[nanodeath]

Presently (in whatever the current version is; can't tell due to #47) there's a single checkbox for controlling the shift key behavior -- "SHIFT as Modifier Key". Especially with "Only Command Keys" enabled, it makes sense to leave this unchecked.

However, this leaves two undesirable options:

1. If "SHIFT as Modifier Key" is checked and "Only Command Keys" is also checked, simply capitalizing any letter will result in a displayed keystroke, which seems silly.
2. Alternatively, if "SHIFT as Modifier Key" is unchecked while "Only Command Keys" remains checked, you get an undesirable behavior: complex keypresses (any involving CTRL or ALT plus SHIFT) end up printing multiple keystrokes to the screen.

What I expect and want is for "Shift-a" to never be displayed (that's just a capital letter), while pressing Ctrl-Shift-A should only result in a single reported keystroke, not Ctrl-Shift followed by Ctrl-Shift-a, but there's no way to do this.

Thanks!