Just started a thread about this amazing compressor. 
For info, I've found kind of a bug in RZM v0.07h: If you try to extract not a RZM packed file, say MPTRACK.EXE, RZM will crash. RZM by default decompresses if first parameter not "c", so if you accidentally type:
rzm e mptrack.exe mptrack.rzm
->
Code:
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RZM 0.07h (Apr 24 2008) - Copyright (c) 2008 by Christian Martelock
Contact: christian.martelock@web.de - TEST version - May contain bugs...
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Decoding 'mptrack.exe' (using 130M memory)
60kb -> 65405kb (66974912b, 108985.59%)
And RZM crashes producing a standard crash window - "Send Error Report"/"Don't Send".