I have built a tcl program using tcldot on MacOS. I have to supply it to someone who uses Windows 7, but I do not have development tools for Windows 7.
The prebuilt binaries for graphviz at http://www.graphviz.org/Download..php for MacOS contain what I need (at /usr/local/lib/graphviz/tcl), but I cannot find the corresponding dll in the prebuilt binary for Windows.
The link at http://www.isn-oldenburg.de/~schlenk/tcl/tcldot/ seems dead.