You should always specify a mask, the --help says:
./sp64.bin [options]... hcstat-file [filter-mask]
the mask (filter-mask) is needed to tell sp64 where you want the --custom-charset1 etc to be used, something like this:
sp64.bin --custom-charset1=?dabcdef --pw-min=10 infinitum10digithex2.hcstat ?1?1?1?1?1?1?1?1?1?1
./sp64.bin [options]... hcstat-file [filter-mask]
the mask (filter-mask) is needed to tell sp64 where you want the --custom-charset1 etc to be used, something like this:
sp64.bin --custom-charset1=?dabcdef --pw-min=10 infinitum10digithex2.hcstat ?1?1?1?1?1?1?1?1?1?1