I'd already done it, but it didn't answer my questions. I tried redownloading Firmata-2.1beta7 but from firmata.org and it worked fine. I dont' know what could happen.
Another question:
It's ok if I modify line 38 of "StandardFirmata" and change the samplingInterval from 19ms to, for instance, 1ms or 0.5ms or it'll be useless or dangerous?
Thanks for your work, it's quite helpful.
Ignacio