Hmm...as to the mass mail not working...if you look at the 2 lines:
PHP Code:
$action = "mailusers";
$action = "forums";
You'll notice that the $action = "forums"; is rewriting the $action variable so that it will no longer mail the users, but go to the forums. So remove the $action = "forums"; line. Also, please do not run this version. It is not complete. Do not use it for your final import. The final version you will obtain from JelSoft (hopefully

).
As to the \'slash\' problems...I do not know what is wrong with that. I'll look into it, but I am not sure what you are talking about.
Also, expect a new release very soon that has much improved HTML2BB decoding.