Awesome not picking config when launched with Gnome Flashback

I recently tried to run Gnome + Awesome cause I got tired on some KDE stuff when trying to have a complete desktop environment with the power of awesome tiling and framework.

This is the piece of code I added for this based on this thread:

      displayManager.gdm.enable = true;
      desktopManager.gnome3 = {
        enable = true;
        flashback.customSessions = [
            wmCommand = "/run/current-system/sw/bin/awesome";
            wmLabel = "Gnome3 + awesome";
            wmName = "gnome3-awesome";
      windowManager.awesome = {
        enable = true;
        luaModules = with pkgs.luaPackages; [

But weird thing is that if I start the Gnome + Awesome session, awesome starts with the default rc.lua and not the user-space one.

Maybe some of you already tried something like this and can provide some guidance?

Thanks in advance.