Logic bug in Vaults of Knowledge 1.6.9 :
In the current version, research can be paid for with 1 dedicated VOK Databank or, alternatively, 2 generic databanks.
The bug: if you have zero generic databanks in the industrial store, you cannot start any research — all the buttons will be greyed out — even if you have some dedicated VOK Databanks.
Workaround: You have to add some generic databanks to the store before you can initiate research. When you press the button, only the dedicated VOK Databank is actually consumed.