Ok, I'm Italian student...

Error:

$HERest -A -D -T 1 -C config -I phones0.mlf -t 250.0 150.0 1000.0 -S train.scp -H hmm1/macros -H hmm1/hmmdefs -M hmm2 monophones0

this command generates a lot of errors.. Read http://labrosa.ee.columbia.edu/doc/HTKBook21/node108.html

for more (realy few) information about HERest..

Anyway, this is the way that go good:

$HERest -A -D -T 1 -C config.txt -I phones0.mlf -t 250.0 150.0 1000.0 -S train.scp -H hmm0/macros.mmf -H hmm0/hmmdefs -M hmm1 monophones0.mlf

Note that:

* After the word config.txt there is the caracter '-' and than the caracter 'I' (i in the uppercase).

* Every file extension are required and some file mast be matched.. ;-)

Have a good lack :)))