Verse Build Error After Republishing UEFN Island

Development Programming & Scripting Verse
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We encountered a persistent Verse build error after making changes to our published UEFN island. Below are the detailed steps, error messages, and troubleshooting steps we have taken so far:

Steps to Reproduce:

  1. Created and published a UEFN island successfully.
  2. Identified some bugs in the live code, fixed them, and attempted to relaunch the UEFN session to test the changes.
  3. Encountered the following Verse build errors when launching the session:

VerseBuild: Error: D:/Uefn/FPS_moshpite/Plugins/FPS_moshpite/sys/published/Content/CustomCounter.verse(9,1, 12,1): Script error 3593: Definition (/gamersroof@fortnite.com/FPS_moshpite:)MakeCountdownTimer is accessible universally, but depends on (/gamersroof@fortnite.com/FPS_moshpite:)countdown_timer, which is only accessible from subpaths of /gamersroof@fortnite.com/FPS_moshpite. The definition should be no more accessible than its dependencies.


### **Root Cause Identified:**

* The error points to an accessibility mismatch where the `MakeCountdownTimer<constructor><public>` function was accessible universally, but it depended on `countdown_timer`, which was only accessible from subpaths.
* To resolve this, I removed the `<public>` declarations from `MakeCountdownTimer<constructor>` and rebuilt the code.

### **Current Issue:**

* After resolving the accessibility issue and successfully rebuilding the Verse code, the error still persists when launching the game session in UEFN.
* This issue did not occur during the initial development or prior to publishing the island. It only started appearing after the island was published.

### **Code Snippets (Before and After Fix):**

**Initial Code (with errors):**

MakeCountdownTimer<constructor><public>(HUDMessageDevice:hud_message_device, MaxTime : int) := countdown_timer: 
    RemainingTime := MaxTime
    MaybeHUDMessageDevice := option{HUDMessageDevice}

MakeCountdownTimer<constructor><public>(MaxTime : int) := countdown_timer: 
    RemainingTime := MaxTime
    MaybeHUDMessageDevice := false

Updated Code (after fix):

MakeCountdownTimer(HUDMessageDevice:hud_message_device, MaxTime : int) := countdown_timer:
RemainingTime := MaxTime
MaybeHUDMessageDevice := option{HUDMessageDevice}

MakeCountdownTimer(MaxTime : int) := countdown_timer:
RemainingTime := MaxTime
MaybeHUDMessageDevice := false


### **Additional Information:**

* Even after fixing the accessibility issue, the error persists during game session launch.
* This problem has occurred previously in another project. Despite posting a bug report about it in the UEFN forums, we have not received any resolution. The previous report can be found here:
[Verse Build Error on Republishing Fall Guys Island After Environment Changes](https://forums.unrealengine.com/t/verse-build-error-on-republishing-fall-guys-island-after-environment-changes/2042620?u=kharey74)

### **Request for Assistance:**

* Why does this issue only arise after publishing the island and not during pre-publishing development?
* How can we resolve the persistent build error when launching the session, despite fixing the code and rebuilding Verse?

We would appreciate any insights or guidance on resolving this issue. Thank you!