Hi,
With compat, in earlier version (1.7.4) I had GLSL compilation issues so in few
application the transform_feedback didn't work. It was related to
GL_ARB_enhanced_layouts, something was telling me it was not usable within a
vertex  shader.

In latest version with compat I had a completly garbled display, there was a
problem when resolving function pointers for GL_ARB_direct_state_access, mainly
glBindTextureUnit, if I remember correctly.

The only way I found was to start with a core profile, and address issues one
by one.