Most Tcl features are present, including many Unix-like features. Additional features include supporting the env variable and sourcing Tcl code from a resource. Numerous ports to DOS are available. A very rudimentary Debugger User Interface using Borland's Classlib is part of the zip-file, too. Unfortunately Ekki doesn't have time currently to finish the Windows port and user Interface.
More details are to follow.
He also was working on a facility for dynamically allocating commands to the Tcl environment. If there are other extensions that one would like to see under Windows 3.1, or if you are interested in beta testing, drop him a line. Someone, whose name I don't have, reported porting Tcl to QNX with a fair amount of hacking. The pathname may be subject to change as I have seen notes from Angel Li mentioning that BLT 1.6 and the photo widget have also been ported. These were compiled on an Alpha running OpenVMS T6.1.