Mounting wifi access point to lath and plaster ceiling
My house was built in the 1890's and is predominantly plaster &amp; lathe. I've mounted everything from small pictures to 10' long by 8' tall shelving to the wall by simply running drywall screws into the wall. I've tried using a stud finder to find studs, but the lathe befuddles them. I simply drive a screw wherever I want to hang something and have never had a problem.
When mounting on plaster and lathe, I'd recommend simply driving screws through the mounting holes and into whatever they find to hit behind them. As small and light as these are, even if all 4 screws only find plaster, they'll still hold just fine.