You can now specify a set of custom step definitions to BIMTester.

src/ifcblenderexport/blenderbim/bim/module/bimtester/__init__.py

@@ -5,6 +5,7 @@ classes = (
     operator.ExecuteBIMTester,
     operator.BIMTesterPurge,
     operator.SelectFeature,
+    operator.SelectSteps,
     operator.SelectBIMTesterIfcFile,
     operator.RejectElement,
     operator.ApproveClass,

src/ifcblenderexport/blenderbim/bim/module/bimtester/operator.py

@@ -29,7 +29,8 @@ class ExecuteBIMTester(bpy.types.Operator):
                 "path": "",
                 "report": report,
                 "schema": "",
-                "lang": "en"
+                "lang": "en",
+                "steps": props.steps
             }
             use_stored_ifc = props.should_load_from_memory and IfcStore.get_file()
             runner = bimtester.run.TestRunner(args["ifc"], ifc=IfcStore.get_file() if use_stored_ifc else None)
@@ -71,6 +72,22 @@ class SelectFeature(bpy.types.Operator):
         return {"RUNNING_MODAL"}
 
 
+class SelectSteps(bpy.types.Operator):
+    bl_idname = "bim.select_steps"
+    bl_label = "Select Steps"
+    filename_ext = ".py"
+    filter_glob: bpy.props.StringProperty(default="*.py", options={"HIDDEN"})
+    filepath: bpy.props.StringProperty(subtype="FILE_PATH")
+
+    def execute(self, context):
+        bpy.context.scene.BimTesterProperties.steps = self.filepath
+        return {"FINISHED"}
+
+    def invoke(self, context, event):
+        context.window_manager.fileselect_add(self)
+        return {"RUNNING_MODAL"}
+
+
 class SelectBIMTesterIfcFile(bpy.types.Operator):
     bl_idname = "bim.select_bimtester_ifc_file"
     bl_label = "Select BIMTester IFC File"

src/ifcblenderexport/blenderbim/bim/module/bimtester/prop.py

@@ -42,6 +42,7 @@ def refreshScenarios(self, context):
 
 class BimTesterProperties(PropertyGroup):
     feature: StringProperty(default="", name="Feature File", update=refreshScenarios)
+    steps: StringProperty(default="", name="Custom Steps")
     ifc_file: StringProperty(default="", name="IFC File")
     audit_ifc_class: EnumProperty(items=getIfcClasses, name="Audit Class")
     qa_reject_element_reason: StringProperty(name="Element Rejection Reason")

src/ifcblenderexport/blenderbim/bim/module/bimtester/ui.py

@@ -28,6 +28,10 @@ class BIM_PT_qa(Panel):
         row.prop(props, "feature")
         row.operator("bim.select_feature", icon="FILE_FOLDER", text="")
 
+        row = self.layout.row(align=True)
+        row.prop(props, "steps")
+        row.operator("bim.select_steps", icon="FILE_FOLDER", text="")
+
         has_ifc_file = (IfcStore.get_file() and props.should_load_from_memory) or (
             props.ifc_file and not props.should_load_from_memory
         )