The stand-alone Above512 Rexx DLL file works like the stand-alone Above512
executable, but only supports the options -c, -u and -!, and returns codes
which may be different in case of an error:

0 - Success
1 - No module name specified
2 - No valid options specified
3 - Cannot open module
4 - Cannot read module
5 - Not a LX format 32-bit module
6 - Cannot write module
7 - Cannot restore date/time attributes
