Okay, I fixed some broken things in ccNotepad and now it seems to be working, more or less. You can
download the new version (1.0.5) here or let Safari update your installed one. After updating, it's a good idea to close all Safari windows or restart Safari to make sure the update is applied.
Please note: For some reason, it takes a couple of seconds for the notepad window to open after you click the toolbar button. This didn't used to happen, and I don't know why it does now. It must be something that Apple changed in Safari.
If the notepad window still won't open for you even with popup blocking turned off, you probably need to use the "alternate window opening method". You can enable this in the Extensions section of Safari preferences — look for ccNotepad in the extension list and select it.
BTW, the way I turned off popup blocking was by going to the Security section of Safari preferences and unchecking "Block pop-up windows".
Chul