I have to admit I was surprised too. I'd never heard of a Lexus featuring diesel, but I was also under the impression that Lexus cars weren't as popular in Western Europe as they are here. I wish diesels were more common place here in America. The only issue with diesel in certain areas is that you have to scope out if there's a petrol station that has diesel. I've driven American big truck diesels but have also driven the old Merc turbo diesels, which give off wonderful clouds of smoke. Usually if you have a diesel in the states, you want to carry mechanics style gloves because the petrol stations have a lot of gunk and grime on the nozzles. Petrol station owners don't seem to care about their cleanliness. I carry a pair in all my cars because even regular gas nozzles are disgusting. After you see drivers doing strange things whilst driving like adjusting themselves or picking their nose, the idea of wearing gloves is fantastic. Especially during the cold/flu season.
You can check out Autopia. I believe they have more European members than other sites. You might have trouble finding some of the stuff we Americans get, but there's a lot of leather conditioners. I've heard of people using BMW's leather cleanser which has a strong leather smell. I've never tried it myself, and instead of opted for various brands over the years. If I can recommend one product for any car owner it's Iron X. I know that's available in Europe. It's a fantastic product to use on wheels and your entire car.
There are polishers made for wheels as well, but I've never curbed my wheels before. One thing with Lexus is that because of how they paint their cars, should something happen, it's difficult to redo certain colors. The white I've got is simple, but if it were sprayed, I'm sure I could tell the different with a halogen lamp. You can google it yourself and see complaints. I've heard Lexus dealers can order you a factory painted panel if you're willing to pony up the difference, but I'm fairly certain that's BS because I've only heard it a few times.
If they haven't given you a time window, I'd simply sit on it. As for cleaning dust on control buttons... I'll be quite honest here, the best brush I've found for those is a soft nylon based mushroom brush. It's not fancy, but it beats any specialized brush I've used.