OP here with an update.
Thanks to all of you who responded, I appreciated all the information. (Sorry the thread was 4+ pages Chr$, but thanks for your input anyway).
I have confirmed with the appraiser that the roof should be OK. He had written it up on the insurance claim for replacing as a proactive measure to bring the trailer up to new condition (as insurance claims are supposed to do). So perhaps a shorter life span but functional and no leaks detected.
The insurer is stating that the title remains as is (i.e. no salvage title) and just the trailer is no longer insurable. Contents are covered by my homeowners policy so I'm OK that the trailer itself is no longer covered.
Based on this, I am taking the salvage value and we will continue to use 'Dimples' until she is has fulfilled her usefulness to us. The insurance money will be invested for our next trailer.
Although the majority of you felt that this was the logical route to take, I appreciated the other points of view (particularly Bruce who stated that it was preferable to replace a written off trailer). This motivated me to think this through carefully and ask more questions regarding the true condition of the trailer. As a result, I feel much more confident of my decision.
Now that the trailer is winterized, I will not need to start any new topics for awhile....except maybe about toilet paper.
Howie