diff --git a/include/sliceDataStorage.h b/include/sliceDataStorage.h
index 0c36cfbc54..749fb8bbbc 100644
--- a/include/sliceDataStorage.h
+++ b/include/sliceDataStorage.h
@@ -399,10 +399,7 @@ class SliceDataStorage : public NoCopy
      */
     SliceDataStorage();
 
-    ~SliceDataStorage()
-    {
-        delete prime_tower_;
-    }
+    ~SliceDataStorage();
 
     /*!
      * Get all outlines within a given layer.
diff --git a/include/utils/LayerVector.h b/include/utils/LayerVector.h
index ab00bbb363..bdf99cd9ca 100644
--- a/include/utils/LayerVector.h
+++ b/include/utils/LayerVector.h
@@ -155,24 +155,24 @@ class LayerVector
         return value_type{};
     }
 
-    [[nodiscard]] LayerIndex getLayer(const const_iterator& iterator) const
+    [[nodiscard]] LayerIndex getLayer(const const_iterator& it) const
     {
-        return std::distance(begin(), iterator) - delta_;
+        return std::distance(begin(), it) - static_cast<difference_type>(delta_);
     }
 
-    [[nodiscard]] LayerIndex getLayer(const iterator& iterator) const
+    [[nodiscard]] LayerIndex getLayer(const iterator& it) const
     {
-        return std::distance(begin(), iterator) - delta_;
+        return std::distance(begin(), it) - static_cast<difference_type>(delta_);
     }
 
-    [[nodiscard]] LayerIndex getLayer(const const_reverse_iterator& iterator) const
+    [[nodiscard]] LayerIndex getLayer(const const_reverse_iterator& it) const
     {
-        return std::distance(iterator, rend()) - 1 - delta_;
+        return std::distance(it, rend()) - 1 - static_cast<difference_type>(delta_);
     }
 
-    [[nodiscard]] LayerIndex getLayer(const reverse_iterator& iterator) const
+    [[nodiscard]] LayerIndex getLayer(const reverse_iterator& it) const
     {
-        return std::distance(iterator, rend()) - 1 - delta_;
+        return std::distance(it, rend()) - 1 - static_cast<difference_type>(delta_);
     }
 
     void pop_back()
diff --git a/src/PrimeTower/PrimeTower.cpp b/src/PrimeTower/PrimeTower.cpp
index 056cf2d9d2..b58b9c7dd7 100644
--- a/src/PrimeTower/PrimeTower.cpp
+++ b/src/PrimeTower/PrimeTower.cpp
@@ -60,8 +60,8 @@ PrimeTower::PrimeTower()
 
         for (coord_t z = 0; z < base_height; z += layer_height)
         {
-            double brim_radius_factor = std::pow((1.0 - static_cast<double>(z) / base_height), base_curve_magnitude);
-            coord_t extra_radius = base_extra_radius * brim_radius_factor;
+            double brim_radius_factor = std::pow((1.0 - static_cast<double>(z) / static_cast<double>(base_height)), base_curve_magnitude);
+            coord_t extra_radius = std::llrint(static_cast<double>(base_extra_radius) * brim_radius_factor);
             base_occupied_outline_.push_back(outer_poly_.offset(extra_radius));
         }
     }
@@ -366,21 +366,24 @@ bool PrimeTower::extruderRequiresPrime(const std::vector<bool>& extruder_is_used
 
 void PrimeTower::gotoStartLocation(LayerPlan& gcode_layer, const size_t extruder_nr) const
 {
-    if (gcode_layer.getLayerNr() != 0)
+    // Layer number may be negative, make it positive (or null) to apply modulo operator
+    LayerIndex layer_nr = gcode_layer.getLayerNr();
+    while (layer_nr < 0)
     {
-        size_t current_start_location_idx = ((((extruder_nr + 1) * gcode_layer.getLayerNr()) % number_of_prime_tower_start_locations_) + number_of_prime_tower_start_locations_)
-                                          % number_of_prime_tower_start_locations_;
-
-        const ClosestPointPolygon wipe_location = prime_tower_start_locations_[current_start_location_idx];
-        const ExtruderTrain& train = Application::getInstance().current_slice_->scene.extruders[extruder_nr];
-        const coord_t inward_dist = train.settings_.get<coord_t>("machine_nozzle_size") * 3 / 2;
-        const coord_t start_dist = train.settings_.get<coord_t>("machine_nozzle_size") * 2;
-        const Point2LL prime_end = PolygonUtils::moveInsideDiagonally(wipe_location, inward_dist);
-        const Point2LL outward_dir = wipe_location.location_ - prime_end;
-        const Point2LL prime_start = wipe_location.location_ + normal(outward_dir, start_dist);
-
-        gcode_layer.addTravel(prime_start);
+        layer_nr += number_of_prime_tower_start_locations_;
     }
+
+    size_t current_start_location_idx = ((extruder_nr + 1) * static_cast<size_t>(layer_nr)) % number_of_prime_tower_start_locations_;
+
+    const ClosestPointPolygon wipe_location = prime_tower_start_locations_[current_start_location_idx];
+    const ExtruderTrain& train = Application::getInstance().current_slice_->scene.extruders[extruder_nr];
+    const coord_t inward_dist = train.settings_.get<coord_t>("machine_nozzle_size") * 3 / 2;
+    const coord_t start_dist = train.settings_.get<coord_t>("machine_nozzle_size") * 2;
+    const Point2LL prime_end = PolygonUtils::moveInsideDiagonally(wipe_location, inward_dist);
+    const Point2LL outward_dir = wipe_location.location_ - prime_end;
+    const Point2LL prime_start = wipe_location.location_ + normal(outward_dir, start_dist);
+
+    gcode_layer.addTravel(prime_start);
 }
 
 } // namespace cura
diff --git a/src/sliceDataStorage.cpp b/src/sliceDataStorage.cpp
index b16b130794..c030fc403d 100644
--- a/src/sliceDataStorage.cpp
+++ b/src/sliceDataStorage.cpp
@@ -270,6 +270,11 @@ SliceDataStorage::SliceDataStorage()
     machine_size.include(machine_max);
 }
 
+SliceDataStorage::~SliceDataStorage()
+{
+    delete prime_tower_;
+}
+
 Shape SliceDataStorage::getLayerOutlines(
     const LayerIndex layer_nr,
     const bool include_support,