Hello,
Sorry to hear you are having issues. Please download and install the latest Start11v6.02.2 (Beta). This version should make arranging icons easier than previous version. You should be able to download from your product account page: https://store.stardock.com/myaccount/products#
As for drag and drop. You just need to click, drag and drop those tile any where you wish. When the "+" sign appear if you release then, it will make those two tiles into one Folder. Just like official Windows 10 Start menu.
There are lots of customization available in Start11v2. Just take your time to learn up on what each function does. What you need to know is that you can back up your setting, so that you can revert back to your previous state if you have done something you don't like.

Thank you.
Basj,
Stardock Community Assistant.