2015_12_19 We had to remove the back scenes.
Despite the fact that we used spray adhesive which meant the paper went on dry, over the next few weeks, the paper rippled and shrunk. We are pretty sure we could iron the bumps out and the paper would return to its original length.
However, unfortunately we could only remove about 90% of each sheet, leaving tears and rips in the rest.
I decided to cut my losses and replace the sheets.
We experimented with some 80gsm paper using white glue diluted 15 to 1 and were pleased with the results. Perhaps that is our answer.
The manufacturer discourages using wall paper paste, telling us to leave unglued gaps between the adhesive, but after seeing the shrinkage we are not happy to do that. The white glue experiment left a perfectly flat secure cover. Perhaps we could seal it with matte liquid medium?