The bit about keyloggers was helpful advice. I went to update my spyware info, but then remembered I actually have an anti-keylogger, so I looked at its list, and it apparently had identified Noteworthy Composer as a hooker (probably because it uses getkeystate). I've had the anti-keylogger for a long time, so I dunno why it suddenly disabled NWC, but I just enabled it and now it works fine. Problem solved.
Well, I tried some things. I tried another keyboard, with no success. I tried another computer entirely, with success. (However, that other computer doesn't currently have midi playback 'cuz of the OS, but that's something else I'll work on some other time.) Stickykeys and the other options in accessibility are off. The thing that Rick G. gave me didn't do anything.
Control up/down doesn't move the cursor an octave, just to the next line/space on the staff. Just as though I was not pressing control at all.
Are the shortcuts for moving octaves, for transposing, and for highlighting menu accelerators? The stem-direction shortcut works, but those other ones don't, which is what really puzzles me. I'd think either they'd all work or they'd all not work.
If I try any of those, it acts as though none of the keys except the arrow was pressed. If I press just right/left when notes are selected, it just deselects them. If I press shift right/left, control shift right/left, it just deselects them--acts exactly the same as if I just pressed right/left. If I press those shortcuts when nothing is selected, the cursor moves right/left. Control or control-shift up/down moves the cursor up/down whether or not notes are selected, and deselects any notes that are selected. Just as if I pressed up/down. Somehow shift up/down works though...
I guess some other key being stuck is a likely possibility. How would I test for that?
I've been using Noteworthy Composer for a while, and up until recently it was working great. However, now a few shortcuts (such as shift right/left to select text, control right/left to skip to the end/beginning of a bar, control shift up/down to transpose) are not functioning, and instead just move my cursor (and deselect any notes I've selected using using the mouse, if I had any selected). Other shortcuts (such as control backspace, control enter, shift up/down) still work. The problems only seem to manifest for this program (shift right/left still work in text-editing programs for selecting text), and even after uninstalling and reinstalling NWC, the problems still persist.
Could anyone suggest any potential cause of this problem, or potential solution? It'd be much appreciated; I'm at a complete loss.