Is it ok to speak polish very badly to someone in Poland even if the other person speaks reasonable english?
Blimey! There's hope for me yet! Don't think i've ever heard Polish spoken so badly!
Having said that Catsoldier, people learn by making mistakes as i'm sure you know.
Even when my Polish was much worse than it is now, i still spoke Polish to people in shops when i was in Poland.
Unless you are fortunate enough to be able to speak Polish on a regular basis, when else are you going to get the chance to practice it?
I've made a fair few howlers speaking it abroad in the past, and probably did make a fool of myself, but by and large most Poles were laughing with me, not at me!
Most will respect you for at least making the effort!