Outside America I think the biggest good-bad movie producing nations are Italy, The Philippines, Hong Kong, Canada and Japan. Indonesia didn't do too badly either (Mystics in Bali, Rambu, Lady Terminator). I'm British and we can't bring much to the table. Technically Superman IV and Howling II are half British, but I don't think anyone's buying that. The best I can think of is one I found recently: Suffer, Little Children. It's not laugh out loud funny but it's terrible and entertaining.
You forgot Turkey.
For British bad movies, what about PSYCHOMANIA? GORGO? FIRE MAIDENS OF OUTER SPACE? SPICE WORLD? Surely Hammer dropped a stinker or two. And wasn't TROG British, even though it starred Joan Crawford? Don't sell your countrymen short!