Digital BW, The Print

I've just downloaded the new versions of QuadTone and the GUI front 
end. Previous version of both worked OK but a couple of problems have 
now appeared. 
Firstly on launching QTRGui I get an "Invalid Floating Point 
operation" error message (although clicking OK lets the program 
start.)
 Secondly drag and drop printing no longer works - I get an !Image 
must be tiff file" message and QTRGui freezes (need task manager to 
kill it). However the same Tif prints OK if the image is selected via 
the menus and then printed.