Might be some repeat:
The 64 LED isn't getting power from the dimmer, right?
Are you using the right profile? Have you skipped the profile and just gone direct to the channel? Profiles are just for us humans to relate easier to the stuff anyways.
The dimmer pack, is it set to dimming or switching per channel? A switching pack would be full on/off, which is what you describe.
PS2(2): There are free DMX packages and DIY dongles. You do get what you pay for.