For the door hinges, you could probably drill the holes out larger and then fill them with thickened epoxy, then re-drill them. I say "probably" not because the concept is questionable, but just because I'm not looking at your hinge setup, nor can I see how extensive the rot is, and you may need to do more.
If the entire piece is rotted it might be better to get in behind the Ensolite and replace it. I'm not sure if it is also encased in
fiberglass, but it might be (that can also be cut out if necessary).
However there is a chance that the moisture is localized and then the overdrill/fill routine would work, and is not too challenging. If you decide to go this way I can explain it in more detail. Photos of your problem area would be helpful.
On the
windows,
Trillium used pieces of plywood, tapered on the edges away from the window so that the Ensolite could rise up gracefully over the wood and be pinched under the window trim. Screws go in from the outside of the window (under those black cosmetic strips - they just pop out), sandwich the
fiberglass, and go into the wood for holding power.
Leaks eventually can rot out the wood.
The fix for that is to remove your
windows, peel back the Ensolite and remove the wood strips, then make new wood strips and reinstall the windows the reverse of how you took it all apart. This is a good time to re-bed your windows (butyl tape works well - the sealant goes under the flange - not around it) and to replace the fasteners with new ones (consider stainless).
Raya