Probably a reboot will fix it. I often need to switch back and forth between Inventor 2012 and 2014. When I do that, add to QAT is also greyed out. After a reboot it is normal again.
SP1 did not fix the ribbon customization settings or the placement settings. I still have to relocate my undocked ribbons off the main screen to me side monitor for many projects and reconfigure the panels too. This has been the case for each and every version of inventor since the ribbon was introduced. I've complained in the past many times to no avail.
I have the same problem. This has been the case for me ever since they introduced the ribbon. It has never been addressed.
Inventor 2014 x64 (latest update)
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