How do I make the year 4 digits when you insert dates?

EmEditor uses the system-wide locale to determine the date formats.

To change it, go to Windows Settings and search for Region settings. You can either change the Regional format or scroll down to Change data formats. (For older Windows, go to Control Panel | Region)

Why is there no ASP configuration?

The ASP syntax is included in the HTML configuration, and the embedded script (usually written in VBScript or JavaScript) will be highlighted according to the VBScript or JavaScript configuration.

CTRL + Mouse Wheel can change the font size, but can you disable this?

Go to Tools | Customize… and open the Mouse page. In the Options list, uncheck CTRL + Wheel to Change Font Size.

Double-clicking a tab causes to create a new window. Can you disable this behavior?

Yes. Go to Tools | Customize… and open the Mouse page. In the On Tabs group and/or Outside of Tabs group, change Left Mouse Button Double-Click to [Undefined].

How to I access the Sort toolbar?

If you right-click on any toolbar, the Sort toolbar should be listed with the other toolbars. If it is not, click on Customize Toolbars…, and click Reset All.