Making a panel in Flash is rather easy, once you find the little bit of information you need. Panels in Flash are just swfs that happen to be in a specific directory.
Windows® 2000 or Windows® XP:
boot drive\Documents and Settings\user\Local Settings\Application Data\Adobe\Flash CS3\language\Configuration\WindowSWF
Mac OS® X:
Macintosh HD/Users/userName/Library/Application Support/Adobe/Flash CS3/language/Configuration/WindowSWF
drop your swf in there, and it should be available in the Windows>Other Panels menu.