Hey, I'm pretty much completely new to mydmx, but I'm encountering pretty much the same problem that subtekk has been working on.
I'm running the latest version of mydmx, have downloaded and installed the 64-bit drivers from the website, and have downloaded the files that chris pickett has been hosting, dropping them into the mydmx folder.
When I attach only 2 38B LED Pro Lights to my dongle, they both just strobe and don't respond to anything from mydmx other than color changes. i've checked the led display for the dmx address, and i believe i've got them correct on the fixtures.
When I have tried attaching my chauvet intimidator 2.0's, they don't respond to mydmx at all.
Any help is much appreciated. Thanks.