Hi @pvnkmrksk,
Please ask debugging questions on http://answers.ros.org.
It looks like the generated executable is named PlotJuggler with two ‘g’. You should be able to run it with: ./devel/lib/plotjuggler/PlotJuggler
rosrun will not find the executable because it is installed in the lib folder and not the bin folder for some reason. To get it working with rorsrun you can change https://github.com/facontidavide/PlotJuggler/blob/master/CMakeLists.txt#L52 to install in bin
then rosrun plotjuggler PlotJuggler should work