Even easier way *chuckles*
Copy dragon_u.ent, dragonj_u.ent, and dragona_u.ent you your resources_override folder. and make a hotkey to them on your desktop.
From your desktop open the one you want to temporarily change, and make a miniscule alteration to the spelling on;
string chardef = "dragona_u_char.def"
string emotedef = "dragona_u_emote.def"
(ancient)
that is of course from the dragona_u.ent file, to make it a hatchling you change dragona to dragonj, to make it an adult you change dragona to dragon...
Eg..
string chardef = "dragon_u_char.def"
string emotedef = "dragon_u_emote.def"
for adult
string chardef = "dragonj_u_char.def"
string emotedef = "dragonj_u_emote.def"
for hatchling
once you have the file in your resources override and linked to your desktop changing models takes about as long as it takes you to close and reopen HZ
BTW.. for a bit of value added mod. on the adult and ancient if you go down and modify;
float takeoffTime = 1.0
to something more like
float takeoffTime = 0.2
you can fly alot faster, note however make the number too low and you will only hop so you may need to fiddle the number up and down to find what works right on your system.
Soraii