Tom,
It seems Luger's real passion was to build and market a semi-automatic rifle. There is some excellent information about it in 'The Dutch Luger', since some archive material survived when Luger offered his design to the Dutch government.
The Luger rifle was, as far as I know, not a toggle-action rifle, but a bolt-action semi-auto.
(update: I was wrong, see my follow-up post
)
Many of his patents for the P08 show a rifle-background, for example the loaded-chamber indicator/ejector patent.
When he was discharged by DWM, in 1919, he took them to court because he didn't want to surrender the rights of his pending projects to DWM, showing he was still designing stuff right until his death some years later.