>Can any damage be caused by changing this value?  In other words,
>could it make a client unable to restore older versions of files? ...
...
>sudo dsmc restore -se=lorenz -pick "/home/staff/tks/lps/Mail/myub" "/tmp/"

No - the absence of the -INActive operand on the dsmc command line does that.  
;-)
Also, make sure your server date/time is correct and verify that the -SErvername
is selecting the right stanza in the client options file.

  Richard Sims, BU