/s# Select strategy. 0:Xtreme(default), 1:Intense, 2:Longest Match, 3:Huffman Only, 4:Uncompressed
Usually the default (/s0) gives the smallest file size and there's no reason to change it. The other strategies run faster at the expense of file size.
/n# Exact number of Huffman blocks (overrides /b#)
/n# is similar to /b# in that it lets you choose the number of blocks. The difference between /n# and /b# is that changing the /n# by +/-1 will always change the number of blocks, whereas changing /b# will not always do that. This makes it a lot easier to do a manual search on the best number of blocks because you don't waste iterations on files that may end up having the same number of blocks.
/r Randomized initial tables (good for many trials with same options)
Whoops... it should say '/rn' next to Randomized. This option randomizes things a bit and causes the resultant file size to vary by a very small percentage (usually a few bytes). You save by running with this option many times. It is a good idea to get all the other settings right before messing with this.