I’m sorry to hear that you are having problems with the Crumble. There a few possible steps to try to resolve the issue.
1) Make sure that the Sparkle is connected correctly. You can use Sparkle Help to assist you with this. I noticed that you mentioned about the red LED on the board. This lights up when the motor output is on.
2) If you have more than one Sparkle, try chaining them together, then addressing them individually (Sparkle(0), Sparkle(1) etc.
3) Make sure that you are not using rechargeable batteries – the green and blue emitter especially, require 4.5v.
4)We can replicate the dim red flashing on a Sparkle, when we remove the negative connection – check that the croc leads you are using, aren’t damaged in any way.
If these still don’t work, it may be worth popping a video/photos of your set up etc. to assist us further.