You must use adb or root explorer to "install" them. You cant just install them like a regular apk.
ADB:
adb push whatever.apk /system/app/ (do the same with the .odex file)
Root explorer:
Just copy the files from your sd to the system folder and reboot.
This ADB Push thing is really difficult!
This is what I've tried and I get an error
Edit: I did the ADB Devices command and it didn't detect my phone. And yes, the phone is in debugging mode.
C:\sdk\tools>adb push TouchWizCalendar.apk /system/app/TouchWizCalendar.apk
error: device not found
I put Touchwizcalendar.apk and odex in tools folder but still doesn't work. Can you walk me through this?