You know, I'm having trouble too with this! On my Ubuntu 13.10 (Unity) machine everything works perfectly, but I tried taking the mods to a Debian machine I set up and got exactly the same login problem as you! The patching went fine (just a little offset that I checked was harmless), but then boom finis. Ugh, I wish I knew what's going on here... :(
I had success activating one change at a time with setxkbmap. Then I tried setting an option in the layout GUI and it crashed badly on me. I'm suspecting that GNOME 3 might be the culprit as it overrides the X defaults in a somewhat fishy manner.
You're probably right that it'd be safer to activate the xkb changes after logon? But it annoys me if that's true...
It may be the many ways that xkb configurations are stored: In /etc/default/keyboard, but also in the Gnome gsetting org.gnome.libgnomekbd.keyboard and in xprop -root. And who knows where else or how these affect each other...
Actually, the options are only guaranteed to work on the first group/layout; this is a shortcoming of XKB as it stands. However, looking at 'setxkbmap -v 9' I see that the symbols component says '+level5(caps_switch_lock)+extend(basic):1+extend(basic):2' at the end even though the 'options' component only has 'misc:extend'. So the extend(basic) set is activated for both the first and second groups! This is because of rules I made in the base/evdev rules files.
I shouldn't think that you need the 'no' (Norwegian) layout at all, but maybe a 'pt' (Portuguese) one or something? Wild guess, but there are many choices on the locale list now.
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