I reported this issue to support@eventide.com but I am not sure if it came through.
System specs:
Windows 8.1, 64-bit
Cubase 8.0.10, 64-bit
This happens with H3000 factory, UltraChannel and UltraReverb (latest version)
I cannot type into any text box.
It is possible to double click on a text box and it seems at first as
if it would be possible to enter a value but it is not possible.
The focus stays on Cubase.
Values can only be edited with the mouse.
Other Plugins (not only Steinberg's) do not show this behaviour.
Best regards