I would be interested to hear from those who have used Eiko Bleicher's FREEZER - positions addressed, types of constraint defined, results achieved?
This sw certainly deals with 7-man positions with blocked Pawns, e.g., 8/3K1kn1/8/5p2/3b1P2/6Q1/8/8 w - - 0 88 (Anand-Costa, 1988, c/o KM, http://www.chesscafe.com/text/mueller50.pdf ).
However, there may be other uses, enabling FREEZER to reach out beyond 7-man endgames.
Best - g