Output window strange behaviour

[ligomilitos]

Hi,
I'm new to vdmx, and testing the demo version to get an idea.

But I'm having a strange issue with the output window: every time I select it or move it it increases size. It still works as output window, sending the chosen video material. No matter what values I give in the workspace inspector/canvas-output controls it keeps growing size...
closing and reopening vdmx won't change the previous session size: it starts from last, already increased, size.

this happens when working with a wacom pen tablet, it seems not to happen working with a wired mouse (meaning that it keeps the funny size but won't grow further).
I'm using an iMac (5,1), ATI RadeonX1600, Intel Core 2 Duo

thanks