That would be "mais laisse les bon temps rouler". In Cajun French, "quand meme" usually means "even though" rather than "but".

"Pain d'mais" is indeed corn bread -- think "maize" for "mais", and I think there could be an umlaut over the letter i, the word "mais" meaning "maize" or "corn" usually has two syllables in Cajun French.

Cajun French has mainly been a spoken language, not written very much til relatively recently (i.e. mid-to late-20th century), and the rules of grammar are much much more relaxed than in France. There are fewer different tenses, for example. And there are some odd ways of expressing things which might be archaic or might have come from crossover from another language, for example, one way of using present tense is to say "Le soleil apres se coucher" which means "the sun is setting" (the Irish sometimes use "after" in this way).

I've seen "roulet" and "rouler". One time in Louisiana, years ago, we amused ourselves by counting all the different ways we saw "boudin" (the sausage) spelled: boo-dan, boodin, bo-dan, boodin, and other variations.

Anyway how you spell rouler doesn't matter. Letting the good times roll is what counts!
Suzy T.