In 1971, a disastrous fire destroyed the castle of the former land commandery of the Order of Teutonic Knights, <i>Alden Biesen</i>. At the last moment, most of the paintings in the buildings were saved. Eight of them, by the 17th-century Liege painter, Walthère Damery, were on panels that had been attached to a ceiling. Extinguishing the fire in the burning panels had caused steam to form on some of them resulting in severe warping. The article describes how the reinforcements were replaced, the steps taken to conserve the paint layer and then to restore it to its original condition according to a series of photographs taken earlier, and the difficult process of cutting away the damaged parts of the supports and milling the remaining material and impregnating it with a 60% PVA and water solution to put it under mechanical pressure to reduce the warping. Grooves were also cut in the panels and oak staves introduced in them to counter the warp. Illustrations of the process are appended. -- AATA