Insomnia and insatiable appetite are the hallmarks of Dex, I would be awake at 4am so just worked my way through lots of trashy TV and worked on some photo books for our wedding and honeymoon! There's no cure for it that I found, just try to be productive!!
I switched to 35mg Pred after coming off Dex at 10 weeks? Was originally prescribed 30mg but I was worried this would not be strong enough? As Bella says weaning is really gradual, but finally coming off all Pred by 24 weeks. Literally by 5 mg per week, but with a plateau in there and some weeks at 2.5mg increments?
Progesterone - again gradually reducing, but off completely by 16 weeks.
Sorry, can't help with the inflammation downstairs, I used 400mg cocoa butter pessaries and not crinone.
Clexane - depends on your personal circumstance, do you have any clotting issues? Stay on your dose and ask your OB his/her opinion at your first appointment.