Welcome back Mike :)
For the transmission fluid your owners manual should confirm but it will either be Toyota T-IV or Toyota AFT WS. Personally I wouldn't use anything other than the genuine Toyota fluid unless you know it is the real OEM equivalent.
The 400h launched with the following colour options:
St Lucia Pearl (White), Platinum Ice (Silver), Aleutian Grey, Astral Black, Persian Quartz (bronze/gold), Cherwell Green and Stafford Blue.
Are you interested just to know the name or do you want to obtain some touch up paint? If the latter then you should use the three character colour code on the VIN plate rather than a name, which is different from country to country, between Lexus and Toyota, and ever dealers refer to certain colours with multiple names.
I'd suggest the keys will operate the locks, however you need to use a lot of force because you have no leverage with such a small handle on the key. The same thing happened with my Father's Prius, he didn't have the strength needed to pull the mechanical locks.
Once you get into the vehicle I'd recommend the battery terminals are checked to make sure they are tight. There have been a couple of members who have experienced this and extra resistance from a loose terminal would make the standby battery life worse.
There is the possibility that completely draining the battery the first time has damaged it and so it's capacity is reduced. I'd investigate getting a new battery under warranty if you cannot leave your vehicle for only 2 weeks.
A dealer wouldn't do this. This type of thing is normally a factory fit option only as the wiring isn't typically in place and it would be very expensive to obtain the genuine parts.
That all changed when the immobiliser became integrated into the main engine ECU, and because Toyota engine ECUs have historically been non-programmable to meant it needed to be replaced. I thought this changed in late 2000 with the new LS430 and facelift GS where firmware updates were possible including key programming. I'm sure I've seen information on the use of Techstream where the dealer needs to obtain a one-time key from head office to unlock the program functionality - maybe that was just in the US and not for European vehicles, or perhaps dealers here just like selling ECUs.
There are different fluids depending on the age of the vehicle. Your owners manual should confirm but I'm 99.9% sure you need T-IV fluid. The switch to WS fluid was around 2004.
5 years life for an OEM battery seems a little short, so you do wonder if prevention device is really working as it should. Do you leave your vehicle for long periods of time?
You can either get one from Toyota/Lexus or go with a Bosch or Duracell battery from Euro Car Parts for about £70 with a 4 to 5 year guarantee.
Possibly the same issue as I described above. My dealer recently removed all the pads, greased and cleaned the friction surfaces to try and stop that noise, which did work for a couple of weeks but now its back again. Need to give my own advise a go to see if it helps.
The US and UK vehicles are essentially the same, may be with a customisation or two disabled on the UK models and a few extra options available in the US. You shouldn't have any problems if the US vehicle is supported.
The loss of coolant combined with white smoke would point more towards head gasket rather than just a leak in the rad/water pump but I'd be surprised if there is actually a problem. The white smoke for example could just be from water formed in the rear silencer burning off as you went up/downhill on the slip road.
Keep an eye on the coolant to see if it drops. If you didn't know the level before the issue then you shouldn't assume it has suddenly dropped.
Comfortable again back in my own car :) although I'm sure I'd be able to find better comfort in the Exec given more time to try different seat positions
This is normally because the hybrid energy recovery is providing most of the braking resistance so the mechanical brakes are just lightly scraping the discs. As a result the mechanical brakes may not be used that much and they rust/glaze making the noise worse. Try braking hard from speed a few times to really use the mechanical pads to help clear them up to see if that helps.
I do hope not, her voice really grates with me and she was part of the old Top Gear that was rightly cancelled. Being married to the Top Gear director probably means she is in with a shout.