The reason it is not playing is because GASP uses a highly advanced Motion Matching system and specific Anim Layers rather than a standard Anim Blueprint (ABP). You cannot just drop the animations into the main ABP.
GASP is built differently and uses Animation Layers for weapons. To get the firing animations to play, follow these steps:
1. Locate the GASP Item Data / Overlay State
GASP switches weapon stances using Overlay States (like Pistol, Rifle, Unarmed).
Find the Data Asset or Item Definition for your pistol inside the GASP folders.
2. Link the Anim Layer
Look for the Anim Layer Class or Linked Anim Graph variable inside that pistol data asset.
You need to create a child of the GASP weapon anim layer, plug your retargeted firing animation into the Weapon Fire state inside it, and assign this layer to your pistol item.
3. Use an 'Anim Montage' for a Quick Fix
If the Layer system is too confusing, you can bypass it for the firing logic.
Right-click your retargeted fire animation and select Create Anim Montage.
Inside the character blueprint where the gun fires, use a Play Anim Montage node, select your new montage, and ensure the Mesh parameter is linked.
Let me know:
* Is your asset currently firing the weapon using a Play Anim Montage node, or is it handled inside your old ABP?
* Does your asset use a specific Slot Name (like UpperBody) for montages?