The downlights in my kitchen have little glass (or plastic) lenses below the bulb. It is not obvious how these should be removed - to change the bulbs. Any advice would be appreciated.
if they are elv halogen down lights or mains halogen (gu 10) then the glass lens is a part of the whole "bulb". if you look closely, most of the time there should be a cir clip holding the lamp in the down light so take it out and the lamp should drop down
if there is no cir clip try twisting the collar of the fitting anti clockwise as sometimes they are held up like that