Hey Blind-Dog I can try to give you some help.
1. Her you could use a droplist or just a plain sprite with the options(like monkey island 3).
2. Currently not worked so mutch with sound, but should not be the biggest problem. Just follow a tutorial like this (http://www.schoolofflash.com/blog/20...ctionscript-3/
3. Here it depends on how mutch information the object has and where you want to store it. (XML, write it in the code, textfile..).
4. Don't need to make a custom cursor, but it would not hurt to add it in the game.
Sorry for the short answer, but it would be alot of codeposting to answer it all. Send me a PM if you want to discuss it more.
Good luck with the game