Can I install plugins to sketchup make?

sorry to ask a silly question maybe, where is the down load link?

Is there a version for sketchup 2013?

I downloaded the newest version of sketchy physics and installed it. I have sketchup pro 8. When sketch up starts i get the following message

Error Loading File sketchyphysics.rb
undefined method extend_object' for Singleton'

then when i try to download and use a sketchy physics model from wharehouse, they dont work and i get the following message.

Error starting the simulation:uninitialized constant. msketchyphysics 3::SP3xSimulationContext::SP Sounds C:/PROGRA~1/google/GOOGLE~3/plugins/sketchyphysics3/controller commands. Rb:777:in 'initialize'

can anyone help me with how i sort this out?

Lucy

i am a beginner and strugling a bit. if someone has some time and patience i would love some help.
Please help me install this script, i downloaded it and saved the rb file in plugins, and also the progress bar, but it dosnt work. can anyone guide me through the steps of installing properly? do i need to install another file from the zip file, there are lots more in another folder with png extentions what are they? do i need them?
Lucy

Thankyou! i got it and got it working