June 2016. Feeling unconventional. Thought I might try EvoStick. I spread it directly on stone/concrete, roughened the underside of Peco100 with 80 grit sandpaper and spread Evostick on that too. Left for about 10 minutes to touch-dry, then pressed track into place, leaving 1mm expansion gaps here and there..... Instantly very firm, and over several weeks still firmly in place. Ballasted a long section in November, and with a good soaking of 50:50 Cementone SBR, set like a rock. Overwintered no problem. Still very firm, no movement, no sign of any baseboards or roofing felt, just ballasted track.