When talking to Riala in the HQ about research, if a research has always been selected she will always end her conversation with "I'm afraid we're busy improving our Tower defenses and we don't have time for new research now."
This is for both the ch 4 and ch5 variations on tabs 3 and 4 of Riala's event.
Examples:
After selecting orc diversification
"We're working to see how much more we can diversify orcs. I'm afraid we're busy improving our Tower defenses and we don't have time for new research now."
After selecting purity research
"Our research program on sexual magic and purity is well underway, and proving quite enjoyable. I'm afraid we're busy improving our Tower defenses and we don't have time for new research now."
After selecting divine research
"It's difficult to see what research we can do, beyond this set... I'm afraid we're busy improving our Tower defenses and we don't have time for new research now."
My understanding is that Riala is only supposed to say that last part if research is blocked after the Erosian war from having too low of a tower score. However, the only check in the code to see if that line should be said is switch 2600 Research available is OFF. Problem being that switch 2600 is set to off anytime a new research is selected in the crystal room, so Riala will currently always say that line (even before the eroisan war has ever happened).
I think there needs to be a new switch during the erosian war evaluation if the tower score is too low that can be checked for.