It is possible to move between inputs using
tab keyboard button? Now I cannot. Do I need to set anything? I have GIMP 2.8.14 on Lubuntu 14.04.
See the picture
Yes you should be able to hit tab to move between controls (GIMP calls them widgets).
In older versions of GIMP you could configure this by going to
File / Preferences / Interface / Hotkeys / Dialogues / Jump to widget
In My GIMP 2.8 the option doesn't appear to be available - but when I hit tab the focus moves from one control to the next.
I would try going to
File / Preferences / Interface /
- then select
Reset keyboard shortcuts to default values
And see if it restores tabbing for you