An Windows application I use requires a long left click on a button.
I didn't manage to do it on a Windows 8 tablet. On Windows 8, a long touch leads to a right click.
Is there a way to change this behavior?
A long click is a right click, it's the same on all Windows 7/8/8.1 Tablets. Holding your finger in the same place for 2 seconds produces a small white box around the finger, this represents a right click.
I'm sorry, I don't think I understand what you're actually asking.