Reply by points:
1. It is possible to start multiple downloads with Folx at a time. For more information, please, visit: http://wiki.eltima.com/knowledge-base/folx/multiple-downloads.html
2. Multiple downloads from services like RapidShare or Hotfiles are possible only if you have premium (paid) account there.
If you have a paid account, you can add several downloads to Folx and Folx will precess them simultaneously.
If you don't have a paid account there, you will be able to download files only one by one without a possibility to resume downloads.
This is not a Folx issue, this is the peculiarity of downloading from services like RapidShare.
3. As far as I understand by "mini graph" you mean Status window ( http://wiki.eltima.com/user-guides/downloader-macos/status-window.html
). Am I correct?
If this is the case, then you can hide it from Folx - main menu -> Window -> Show/Hide Status Window.