I used a 1 lb /.45kg hammer and hit both brake mounting plates before
7am to the neigbors delight. The first side released after hammering.
The second side was harder, I hammered but it did not release until
after rolling the trailer back and forth. The top shoe was jamming on
that side. I could see that the lower shoe was not in contact with
the drum.

All in all it turned out to be just a few minutes and all is good
now. I did not have to jack up the trailer or take the wheels off.
Thankfully I got lots of good advice from RAS.
I should get better gas mileage with wheels that turn.

The trailer has been sheltered from rain. All this rusting must have
just been from 2 months humidity [in ample supply].

I did not find a slot to adjust a star wheel. I have done that on
cars in the past so I know what to look for. This design has 2 slots
but they are for the spring to hook through.

I never did figure out what the bolt was for, shown in the 2 o'clock
position in the photo:

http://gliderpilot.org/Temporary

On both sides there were small viewing holes to see if the shoe was in
contact with the drum [shown in the 10 & 5 o'clock position]

I suppose I should soon take the drums off and lubricate the sides of
the shoes/mechanism [not the face that touches the drum].
I don't know if the mechanism or the face of the shoe and the drum
surface that rusted together.

Thanks guys!
Chris