Well, I have no idea what you're copying over what... but if the template from our default package works, that's goes far beyond default miniBB trouble :)

Okay, I think I won't tell you again my reason, bescause I'm at the end of my English ;-)
But thanks for your help and I hope it will work with this solution in the future.

It's only important to find the key to the problem, actually why files are stored on server without having newlines. Maybe it's kind of weird compression on the fly?

I have no ideas...

I have no reason. Maybe the problem is on the server, if so there's a problem with the bplaced server and the newlines?

The problem is not on the server, because as I see, your current version of main_posts.html has newlines. And it's on the server. The problem is somewhere in transmission the file from your disk to the server, or unpacking the file, or...? I have no ideas...