After successful installation and unchecking multisite support I get either no change in the templates at all or, if I assign a template manually to - for instance - the startsite I get nothing but a white screen with the Errormessage "Incorrect usage of Joomlamobile" which is the same I see in the preview of each "*_mobile"-template in the backend.

So what can I do to get Joomlamobile working and the templates shown through a smartphone?
best fahl5

Have a look at this thread. It is quite long but it may help.
www.mobilejoomla.com/forum/topic.html?id=505
I'm not sure how multi site domain is switched on and off, but I was able to get my site to recognise firefox with a user agent switcher both with pda.mysite.com and with a blank in the field "Domain name" found at
Components > Kuneri mobile Joomla! > Settings > Global Settings > Smartphone (XHTML-MP/WAP2.0) Domain

Yes I found the same Error messages cited in this thread, but the problem already starts in the template-preview of my site-backend. Far from discussing any smartphonetype the simple template even dont work in the preview. I didn't found anything like that in the long thread you cited.
If the domain is empty or the one of the startsite does not affect anything. Neither the iphonetester nor my win-mobile show anything else but the bizcity_ii-template.
So in short the mobile-Templates dont work here at all. In so far I dont have even a chance to test what esle doesn't work to. It is really a pitty, since it would be really great if this component would really do what it promises.
best
fahl5