Just downloaded the 2.5 dev. I'll be playing the game as time allows, but I wanted to give some feedback on the new opening.
First, I know that someone put a lot of work into it. I appreciate that, really I do.
That said... it's tedious and dull. It takes three days for current ships to move from the Moon to the Earth, but we needn't actually see aliens doing the same. The opening video goes on for way too long, interrupts the flow of music, and undermines the sense of dread that the original model of load screen to menu provided.
Also, unless something has changed, discerning that the aliens weren't already present in the solar system was (as of 2.4) something that it took research to discover. Showing the aliens folding into existence behind the moon in the opening video rather eliminates the suspense of this - and doing it just so we can see four alien ships very ponderously make their way to Earth and fly around it a few times doesn't strike me as a value-add.
Take a page from the making of Jaws: suspense is best created through music without showing the aliens until later. UFOAI, unlike the original X-Com, actually makes the aliens scary. Stick with that and drop the space opera.