Looks like you didn't see the note about what should be posted here. Please read the note at http://forums.adobe.com/community/robohelp/robohelp_flash where you will see this is not the place to get help on using Flash.
Your post can be moved to either of the locations shown there or to http://forums.adobe.com/community/production_studio
Tell us which one and we will move it.
I am assuming your mouse works for all other applications. If not it sounds more like a Dell issue.
See www.grainge.org for RoboHelp and Authoring tips
As my colleague Peter kindly indicated, you are in the wrong forum to get help for Flash. However, I've been attempting to learn Flash myself so this may be a reasonably simple solution. In flash, some buttons actually have other functions. For these buttons, you click and hold the mouse button briefly to activate the flyout menu.
Good luck with finding a solution to your issue.
My apologies. This is my first time using the forum and I'm afraid I found it a bit confusing. The location shown in the message would be fine. Thank you!
I just now moved your thread to the Flash forum.
Cheers and good luck! Rick