I will travel to the Highlands and have a very quick stop-over at the Glasgow Airport since I have to catch the bus from Daluir. Is there any chance to get alcohol-fuel for a burner? In some countries Methylated Spirits is available in pharmacy shops but I am not sure if this is the case in Scotland and if there is a pharmacy in the airport area
Your travel to Scotland has probably passed, hope you had a good time. You are in the land of my favorite single malts: glendronach, oban, and glenmorangie - and therein lies my answer:
Use ethyl alcohol in a pinch. That is, any high-proof potable spirit, generally anything 75% or more alcohol. Rum, for example, is often used for flambé, and any 151 proof or better is typically used. Any rums, whiskeys, tequilas, gins, etc are expensive compared to vodka, so, vodka or grain alcohol would be the cheap option to go with.
Avoid using dirty alcohols, like isopropyl, they can be sooty and toxic.
The nice thing about using ethyl alcohol is that when you're done, well, it doesn't have to go to waste: Slainte! But with methyl alcohol, the best you can do is use it for a hand sanitizer (isopropyl), or, burn it off otherwise.
Actually, when you are in an area where use of methylated spirits might be available, but you are not aware of your location's regulations on manufacture or use, using that spirit could prove dangerous, whereas liquor store spirits is always safe.