A few questions about deployment projects in .NET

I have created a deployment project to install my media player I have been working on. I have added to custom dialogs. The first one allows the user to choose if the media player will be the primary media player for the listed media types. The checkbox names are "CHKBOX_AVI", "CHKBOX_MP3", and "CHKBOX_MPEG". If the user checks these, I want my project to be associated with those files. Now I have created a 'File Type' for each one of those kinds of files.

For example, here is the info for the mp3 file type:
name: mp3
Command: Primary output from Dave's Media Player (Active)
Description:
Extensions: mp3
Icon: (Icon)
MIME:

and as for the &open thing:
Name: &Open
Arguments: "%1"
Verb: open

First of all, that does not successfully associate my program with mp3 files. What do I need to change? Also, where would I create the condition for making the selected file types associated with my program?


Now for my second related question...
I have another form that allows the user to create a desktop shortcut or not via a checkbox called "CHKBOX_SHORTCUT". Now in my 'File System' page, I selected the 'Users Desktop' folder and opened up the properties menu. My question is what would the condition be to see if "CHKBOX_SHORTCUT" is checked or not?

Sorry if my questions seem stupid, I just need help. Thanks a ton!