The Delete and Backspace keys aren't the same function. Otherwise, only one key would be needed. Delete is a forward delete: delete the character following the cursor. Backspace is a backwards delete: delete the character preceding the cursor.
The Home key positions the cursor to the beginning of the line, preceding all text. The End key moves the cursor to the end of the line (past the last character.) If you want to delete the third digit of three, either place the cursor before that digit and press Delete or after that digit and press Backspace.
If you hold the shift key when using Home or End, you will select all the characters between the cursor's current position and the Home or End position. You might check that you don't have a sticky keyboard or one that "bounces."
LOOOL I don't need history lesson how to use keyboard. I'm stating FACTS, which are pure bugs in Fireworks.
You could have mention in this history lesson how Fireworks is known product with many bugs in its history.
Obviously this "feature" hasn't been changed.
You said, "Inside Properies panel Delete button on keyboard sometimes doesn't work at all same as Backspace." All I can do is respond to what you say. If you don't write clearly, then people will misunderstand what you say.
That said, this is a user-to-user forum. If you want to report a bug, click on the "Contact Adobe" link at the bottom of the page, select the "Feedback" tab, then the "Report a bug" link, and follow the instructions.