Q&A: Into which phase would I put n-acetyl glucosamine? Is there a limit to the size of the cool down phase?

In the March Q&A, Olja asked, My question is about NAG (N-acetyl glucosamine). To which phase do you put it. If you put it to the cool down phase, do you dissolve it prior? Can you dissolve it in a glicerite extract (which also contains some water) and than put it in the lotion? Moreover, if using…