It works

mods/ShopMod.properties

@@ -2,6 +2,18 @@ classname=mod.treestar.shopmod.ShopMod
 classpath=ShopMod.jar
 sharedClassLoader=true
 
-# Activates the json item provider and loads items from the given configuration
-jsonItemProvider=true
-jsonItemProviderItems=mods/shop_items.json
+# Display name shown in the shop window
+shopName=Server Shop
+
+# Allow opening the shop from settlement tokens
+enableTokenAccess=true
+
+# Allow opening the shop from mailboxes
+enableMailboxAccess=false
+
+# JSON config files for categories and items
+categoryJsonPath=mods/shop_categories.json
+itemJsonPath=mods/shop_items.json
+
+# java.util.logging level for this mod (e.g., INFO, FINE)
+logLevel=INFO