It's really hard to believe that the Mysterons didn't notice their Gravener had been killed.

I think what you've said is key to the series' premise - the Mysterons' great powers are offset by their arrogance and lack of perception.

And I think the crash of the XK107 should definitely have set off the nuclear missile, or at least spread a lot of radiation around.

I appreciate that series set in the future have to try to make themselves sound futuristic and ultra-scientific, but comments like Colonel White’s “I’ll be in the Room of Sleep” just make me giggle!

When the Mysteron Gravener arrived at Slaton Airbase and approached the sergeant, was it only me who looked at the latter and said, “It’s Harrison Ford!”?

The Complete Book Of Captain Scarlet says that the disused airfield is a called WESTON but according to the sign it is called WESTERN

No Callie, I said, 'Drat, not him again'

I recently bought the DVD collection of Captain Scarlet, and I've really enjoyed seeing the episodes uncut--and so clear!

One odd thing about this episode--in all the others that I've seen so far (I'm down to the last two) I could immediately recognize what had been trimmed from the scenes for syndication. However, this episode seemed exactly like what I saw on the Sci Fi channel several years ago. Perhaps they simply trimmed seconds off the scenes here and there, but I was disappointed at not seeing anything really new.

One problem with resurrecting the Major--once you're dead, cells immediately begin to die off. The Major was dead for almost two hours, although for most of that time he was on life support. They really should have set this episode in the winter, and tossed in a comment on the water being cold enough to retard cell damage (as sometimes happens in the present day with people retrieved from icy waters).
Actually the Major probably did lose some brain cells--he seemed to totally forget about his driver, Harris, until he saw the retrometabilized copy.

I'd like to know more about this "Room of Sleep." Is it a unisex dormitory? Was Col. White in there sleeping next to an off-duty Angel?

In a prior episode--"Point 738", or whatever the number was--they showed one of the Mysteronized officers listening to Captain Black, while standing in a room filled with people. Obviously, he was the only one who heard Black, so the voice must have been in his head. Other episodes, such as the pilot episode, also make it seem likely that the Mysterons' instructions are relayed telepathically. If this is the case, then, A) How did the real Gravener hear Captain Black's voice, and B) How did Spectrum hear it over the radio?

Given the trauma that Major Gravener went through, I hardly think that the doctors would clear him as fit for duty the very next day. Aside from anything else, the forcible life support would have left him pretty sore. (CPR often ends up breaking the patient's ribs.)

Would a Major really have the authority to requisition a nuclear warhead?

The scenes showing Spectrum preparing their trap were quite effective--such as Lt. Green silently mouthing instructions to someone while we see Col. White studying a display in the background. (Or perhaps he's having a quick nap--he couldn't have spent much time in that Room of Sleep!)

Captains Scarlet and Blue were taking quite a chance blocking an entrance with their Saloon car. That truck could probably have plowed right into them and kept going. (If it had, Captain Scarlet would have taken the brunt of the damage, being on the side facing the truck.)

Major Gravener was lucky that he didn't wreck his plane avoiding that truck. Good pilot's reflexes.