Originally Posted by theducks
Does not matter why! We can't discuss those tools.
Go where you got them and ask for help.
Who do you ask for help when clicking the "Load plugin from file" button causes calibre to close before you've ever even selected any
plugin file (sanctioned or otherwise)?
Try running calibre in debug mode
from a command line and see if any errors get printed out when you click the "Load plugin from file" button and calibre "goes away."