Since all other formatting keys are plain Ctrl+<character> combinations (except Ctrl+-) using Ctrl+D to delete formatting and using Ctrl+Delete to delete the record seems a perfect change :)

Since Ctrl+BkSp does select all notes with similar tags, Alt+BkSp could do the reverse. Well, not really, but Alt+BkSp could be used to clear all filters. The key is not yet used.

Because Ctrl+Delete is already used for removing any formatting ;)

Instead of a button and Alt+D the shortcut "Ctrl+D" will do. This is a common shortcut in other applications as well. Since there would be no gui element at all, a dialog "delete yes/no" would be mandatory. This would be the minimum requirement to delete the active note.

Actually it isn't possible to open the same note multiple times. At least it shouldn't. When you have a note opened, cn will detect and jump to that editor window automatically. However there is a known bug, when you create a note, save changes using Ctrl+S you can indeed open it a second time. This bug will be fixed in v1.6.

When adding a button "delete" the shortcut should be Alt+D, which suits well to Alt+C for "cancel".

What if CN would support drag&drop? That is double click the word and drag it to the tags field?

[EDIT]Another option would be to use Alt+double-click. Actually i think both methods could be added, seems nice to me.

Double clicking is already used for selecting a word. If you really like this feature, make it optional.

Right now, after closing a note, we have different behaviour for similar actions:

1. search for a term, select a note, open and close the note. First ESC will clear the search box. Second ESC will close the main window.
   
2. Don't search a term, just scroll to a note directly, open and close the note. First ESC will close the main window immediately.
   
3. Select a tag, select a note, open and close the note. First ESC will clear the search box. Second ESC will close the main window.
4. Select a tag, search a term, select a note, open and close the note. Now you have three ESC's to first clear the search filter, second clear the tag and third close the main window.

Pressing any character will clear the search filter implicitly. Introducing a shortcut to clear the search filter is not a must. Thus the main benefit of backspace is the explicit clearing of a tag filter, right? However, to not confuse users, the backspace key should reset tag and search filters together. Also backspace should focus the top of the search list as a mean of resetting all together.

Possible Changes:

1. The behaviour of the ESC key should be changed, to always leaves focus on the last edited note.
2. The backspace-key will be introduced with three actions included, a) clear the search filter, (b) clear any tags and (c) jump to the top of the search list. Thus backspace is a global reset function.

Summary:

With those changes the user has more control over the GUI. While ESC does things step by step, BACKSPACE allows to easily and directly reset. Also with the existing Alt+X key the main window can be closed any time.

Fine. Though Backspace is just another shortcut for Home, isn't it?