Hi,
In the first post, the problem isn't so much that the preview has gone small as there is a problem where the whole preview/node network split pane area has gone much smaller than it should - it should be filling that whole right-hand area. This is mostly likely due to a problem when the window is minimised, which I'll look into further.
There was a change in the last version where the preview area was given a minimum size and the more general issue with the preview going "mini" is related to this, in that for some reason it's snapping to its minimum size. It should be resizeable using the splitter bar though. I'll look into this. I think we released the last version not long before I was on holiday for three weeks, and just at the end of that time the monitor I use for my PC died and the replacement only turned up on Tuesday, so I'm still catching up a bit with things on the PC side.
Regards,
Jo