Touch Input Doesn't Immediately Update Mouse Position in Custom Drag System (UE 5.4)

Development Programming & Scripting
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I’m developing a custom drag system in UMG for a VR/UI project in Unreal Engine 5.4.4. It works perfectly with mouse input, but I’m having issues when using touch input on a mobile device or touchscreen.

How My System Works (Mouse - Fully Functional)

  1. I have a main UI widget (WBP_GaleriaGeral) containing a ScrollBox with dynamically generated buttons (WBP_GaleriaIcon).
  2. When I press a button inside the ScrollBox, a new image widget (WBP_ImageDrag) is created at the mouse position and added to the viewport.
  3. Inside WBP_ImageDrag, there is a Tick event that updates the widget’s position to follow the mouse as long as a boolean (AllowDrag) is true.
  4. AllowDrag is set to true in Construct and on Mouse Button Down, and set to false on Mouse Button Up.

Problem with Touch Input

  • When I touch a button (WBP_GaleriaIcon) to create the image widget (WBP_ImageDrag), the first touch always uses the last known mouse position, not the actual touch position.
  • This means the first spawned WBP_ImageDrag appears in the wrong place, often far from the touch location.
  • I tried overriding On Touch Started and On Touch Ended to manually set AllowDrag = true/false, just like I do with the mouse, but the issue remains.
  • After the first touch, dragging works correctly, meaning that Unreal isn’t recognizing the new touch input as a position update immediately.

What I Tried (Without Success)

  1. Manually setting the mouse position to the touch position right before creating WBP_ImageDrag.
  2. Forcing a “mouse move” event when touch starts.
  3. Using “Convert Screen Location to World Space” to update the position before spawning WBP_ImageDrag.
  4. Calling “Set Input Mode Game and UI” when touch starts.
  5. Checking “Use Mouse for Touch” in Project Settings → Input.

What I Need Help With

  • How can I ensure that the first touch correctly updates the mouse position before spawning the widget?
  • Is there a way to force Unreal to recognize the touch location immediately upon pressing?
  • Am I missing a step to properly synchronize touch input and mouse position in UMG?

Thanks in advance for any help!