If you're using LBML there's a new update out. The problem is the updater may not finish updating the program properly rendering the program unable to start or respond when you hit P. If you encounter this problem, restart your computer (or quit the LBML process in the Task Manager if you know how to do that). Then find your LBML folder and open the "updates" folder inside it. Extract the LBMLv0.9.3.3.zip file into the main LBML folder. Start LBML and it should work now, but you'll have to set your settings again. Note that this update now recognizes the ark rares so it's a good one to get.
That happens to me too occasionally. Try going to filters and selecting rocktropia then select Arkadia. If that doesn't fix it then restart LBML.