[xcrysden] xcrysden-1.5.53-bin-cygwin under cygwin

[Danilo Addari]

Dear all,
I'm having troubles in running xcrysden 1.5.53 under the current release
of cygwin (O.S. windows 7 pro 64 bit 6 Mb RAM). The program starts but gives the
following error message:
ERROR: while executing exec /xcrysden-1.5.53-bin-cygwin/binftnunit
couldn't fork child process resource temporary unavailable
It looks as there is something wrong with Tcl/Tk (version 8.5 currently
installed).

Xcrysden is unable to open any kind of file.

Can someone help me please?
Regards