Earlier today I ran into the "too long string of numbers" problem with Plugsound and I remembered that I had stumbled on a workaround back when the software was first released. Doubt that it will work for Charlie but if you don't mind the nag screens, there are two ways that you can use Plugsound in perpetuity. The first is to go into the preferences folder and delete the invisible PS-0whatever file every few days. This will reset the demo counter. Another option is to use something like filebuddy to lock the file. Then it'll stay at whatever day count you are at forever.
I wasn't sure I remembered the workaround properly but I tested it today by installing it, launching it, cranking the calendar forward and, with the locked pref file, it stayed at 15.
D.