The Cygwin version of LMPC needs a special run-time DLL. In the README file of your copy of LMPC you find the version number of the DLL you need.
Copy the DLL in your windows\system directory or better in the directory, where you placed the binaries lmpc32.exe, demcut32.exe, or dbs32.exe.
3/4/2006, Uwe Girlich (uwe@half-empty.de)