Hey,
I use some pretty big VSTs sometimes and the plug in window will not allow me to resize it to accommodate them. Here is a screen shot to show you what I mean. I have to use the scroll bars which is VERY annoying.
Hey, I get this problem sometimes in reaktor too.
In reaktor press the Magnifying glass icon (to close the browser) this will resize the plugin window.
What your screenshot shows is a problem with Reaktor, not Renoise. What Jenoki mentioned should work…you might also want to change the default Reaktor auto size settings to something larger.
Reaktor 5 is the worst at this.
It works fine if you adjust the settings correctly as I suggested above.