If you plan on upgrading to 5.6 or want to be ready for any future upgrades, I would recommend applying the following fix as well
Go to EasyHudBuilder/Core/GlobalConfig and open the DA_EHB_GlobalHudConfig asset

In the list of variables, locate the variable HudModulesDefinitionDataAsset

Click on the Variable Type to open the type dropdown, then replace this type by the following type: Primary Data Asset > Soft Object Reference
Make sure to exactly match this variable type

Then, Compile and Save the blueprint after making this change
Then, go to EasyHudBuilder/Core/ and open the AC_EasyHudBuilderManager asset
Locate the Retrieve Modules Definition node and open it

In this node, remove entirely the set variable Hud Modules Definition Data Asset node

Then make sure to reconnect all the pins like so:

Recompile and Save all the blueprints you modified if you hadn’t done it before and you should now be safe from any compilation errors coming from the pack.
If you still encounter the same errors, you might need to delete your project temporary folders: Saved / Intermediate / Build

If you encounter any other compilation issues, do not hesitate to contact me on Discord or by email.