Usually when there's an error in TntMPD, an error dialog with several reporting options is available with helpful error details. Sometimes (rarely) the error is so bad that Windows will simply tell you that TntMPD crashed, or worse, TntMPD will simply dissapear.
When this happens, you should check the Windows event log. TntMPD (2.1 r21 or newer) will report errors to the "Windows \ Application" section, and the error report might have made it there even though it didn't reach the error dialog.
There's another way to collect an error report that will help TntWare track down the bug. Using tools found in Windows, you can collect a "mini dump" that will help diagnose the crash. It provides a frozen state of the application at the time of the crash and it's usually quite helpful in tracking down the issue.
The "mini dump" can be quite large (several mega bytes), so it's best to send it using a free service like www.yousendit.com to troy.wolbrink@tntware.com. By using this service, you keep my email inbox from reaching its limit.
To get a mini dump under Windows XP, follow the instructions found here.
To get a mini dump under Windows Vista or newer, follow the instructions found here. (Attached and zipped is a .reg file I use to setup mini dumps for TntMPD to the "%LOCALAPPDATA%\CrashDumps\TntMPD" folder.) 1682.TntMPD_Dump_Reg.zip