Lack of resources message

Check the disposition of the population. If there are no people there or they are rioting you will get a 'lack of resources' message.

Kerry-

"...I say we must move forward, not backward, upward, but forward, and always twirling, twirling, twirling towards freedom!"
-Kodos for President

I think you also get this message when you have reached your ship/unit maximum set at the beginning of the game. I've run into that too and it also gives the 'resources' false message.

Kerry-

"...I say we must move forward, not backward, upward, but forward, and always twirling, twirling, twirling towards freedom!"
-Kodos for President

Thats odd. Have you checked that you are actually producing a surplus of each resource? Maybe that has something to do with it (doubt it though). Go into the empire screen, there should be a tally there of how much you have, and how much is spent on various projects.
_______________________
There are 10 types of people in the world:

Those that understand binary, and those that don't.

I can confirm this problem and after some trials I believe I know the reason:
If you need the traded resources for the construction and you have only few resource storage capacity you get this bug. If you just increase the storage capacity it will go away. Therefore probably SE V first makes the construction from the resources the empire itself produces and the resources that are stored. If this is not sufficient, the construction is stopped. After that you receive the traded resources which will then refill your storages and therefore you get the lack of resources messages in spite of filled resource storage.
IMO this is a bug but at least you should know clearly that trade is only effective if you have sufficient resource storage capacity.