How to make gauges is a very general question, that doesn't have an easy answer.
I will walk you through changing one of the pre-made gauges into another, then you can post back with any other questions.
Open default.dxl in the DashXL Editor.
Make sure the 2 "Dashboad Object XXX" windows are open. (If not you can toggle them from the View menu)
Expand the top layer, and then expand "Speedometer". (We are using this because its at the bottom, and easy to find)
You will now see all of the different
background elements of the Speedometer gauge.
-Try selecting different ones, and unchecking the Visible box in the "Dashboard Object Properties" window. This will let you see how these different elements contribute to the final look of the gauge.
Select the element "Text".
In the Object Properties, there is a setting called "Format String". Change this to change the gauge label. (Lets change it to "Throttle Position for now)
Now expand the bottom layer, and the Speedometer container.
Change the text to be "%.0f%", "%.0f" means use the OBD-II value of the PID here (selected below, make sure Use OBD-II value box is checked), the other "%" is because Throttle position is in percent.
Go to the needle object, and change the Range End to be 100 (can't go higher than 100%!!)
In both the Text, and the Needle, change the PID (near the bottom of "Object Properties") to be "SAE.TP".
You just changed the MPH gauge to measure the Throttle Position. Congratulations!
