Sorry, I misunderstood the question. I thought you’d like to use raw GLFW and ModernGL. If you just wanna replace GLWindow with GLFW, then combining the simplest example in Videre with GLAbstraction will be enough to do the job.
The LazyShader and the render abstraction stuff are just certain abstractions over the ModernGL’s basic utilities, they have nothing to do with the advanced modern GL shaders. This recalls the old days when I was learning ModernGL with Julia. Back then, GLAbstraction has some fancy dependencies like Mustache for handling GLSL version. As a beginner, I found these abstraction-only stuff are noisy and it’s actually easier and effective to start with raw ModernGL APIs and build a glutils file with helper functions gradually. But it looks like your specific question is how to fix the example in the GLAbstraction repo. I’d say you will get more helpful responses if you file an issue to the GLAbstraction repo. 
Unfortunately, these examples in Videre are intentionally not using any abstraction layers like GLAbstraction. There is only a glutils.jl file that contains some helper functions for compiling shader, linking GLSL program, creating GLFW window, etc.