Get there quick if you haven't seen it yet. If you have items on display, you need to remove them before the end of July. Magazine Index Bob Moulton has an index on his computer of articles in Railroad modeling magazines. Call him if you want a printout of a search on a topic you are interested in. Last year Bob Batson gave an excellent clinic on constructing rock work on his N-Scale layout.
Mountains formed of plaster can get very heavy.
A support must be created to shape and hold the finished scenery. I use cardboard strips cut to a width of about one inch. I tried different types of wire screens but found them much too difficult to manipulate. I cut out the cardboard strips from old cardboard boxes with a box-cutter. I space the strips about six inches apart.