(CFFI::FL-ERROR "Unable to load foreign library (~A).~% ~A" GLIB::GLIB "Error opening shared object \"libglib-2.0-0.dll\": ..)

[trayres]

I tried the following:
(ql:quickload "cl-cffi-gtk")

Trying:

cffi:*foreign-library-directories*
Nil

I'm not sure if quicklisp or Portacle is having the problem; I believe you can get around it by setting up the FFI library path relative to Portacle root dir, but I haven't tried it yet (first time I've really tried CL is Portacle! It's amazing!)

[Shinmera]

I doubt that this has much of anything to do with Portacle. It looks much more like it's just an issue of CFFI not being able to find the needed library on your system. Are you sure that it's indeed installed?

[ukari]

you could set cffi:*foreign-library-directories* by yourself, like the following example

(pushnew #p"c:/Windows/System32/" cffi:*foreign-library-directories* :test #'equal)
(cffi:load-foreign-library "the-dll-you-miss.dll")

Here is the link