Re: Almost 8 y.o. recently diagnosed, a few questions
I do hope Paddy is feeling better by now. I, too, am glad he was able to gain a little weight and hope his appetite stays steady.
I used the combo of lignans and melatonin with my Squirt for a while when she was first diagnosed. Her cortisol was normal but more than 2 of her intermediates were elevated so that is the treatment recommended. When we started the only lignans available were the SDG, or flax, lignans. When the HMR, or spruce, lignans came out I thought it was worth a try to switch. When we did we lost control of the hormones so we switched back to the SDG and remained with them for the duration. When her cortisol started to rise we used a maintenance dose of Lysodren and just skipped the loading phase. This worked for her but has not worked for all pups who started out Atypical then developed conventional Cushing's (with elevated cortisol). Many many dogs do very well with the HMR so it is definitely worth a shot to start out with them vs the SDG.
I am a Lyso girl through and through UNLESS the dog has the adrenal form of Cushing's then Vetoryl is best because of the need for steadily increasing doses as time goes by (high doses of Lyso can be very very hard on the digestive system). Otherwise, I will always choose Lysodren over Vetoryl. And yes, I am an oddball. 
Looking forward to the next update on our sweet boy!
Hugs,
Leslie
"May you know that absence is full of tender presence and that nothing is ever lost or forgotten." John O'Donahue, "Eternal Echoes"
Death is not a changing of worlds as most imagine, as much as the walls of this world infinitely expanding.