diff --git a/GUI/Model/Descriptor/DoubleProperty.cpp b/GUI/Model/Descriptor/DoubleProperty.cpp
index 4313409db3777453a9d4d5cfb022ae71e961ed43..af005f17da52f7d3c1a43f7944403e6179f76bde 100644
--- a/GUI/Model/Descriptor/DoubleProperty.cpp
+++ b/GUI/Model/Descriptor/DoubleProperty.cpp
@@ -43,7 +43,10 @@ void DoubleProperty::init(const QString& label, const QString& tooltip, double v
     m_step = step;
     m_limits = limits;
 
-    m_uid = uidPrefix + "/" + QUuid::createUuid().toString();
+    if(uidPrefix.size()>0)
+        m_uid = uidPrefix + "/" + QUuid::createUuid().toString();
+    else
+        m_uid = QUuid::createUuid().toString();
 
     m_descriptor.label = label;
     m_descriptor.tooltip = tooltip;
diff --git a/GUI/Model/Sample/InterferenceItems.cpp b/GUI/Model/Sample/InterferenceItems.cpp
index a8ed565c14b811213bf20f174873b6b63fc92915..7a468a6180941ca2ab590689cbff49618ff330b1 100644
--- a/GUI/Model/Sample/InterferenceItems.cpp
+++ b/GUI/Model/Sample/InterferenceItems.cpp
@@ -307,7 +307,7 @@ InterferenceHardDiskItem::InterferenceHardDiskItem()
 {
     m_radius.init("Radius", "Hard disk radius", 5.0, Unit::nanometer, "radius");
     m_density.init("Total particle density", "Particle density in particles per area", 0.002,
-                   Unit::nanometerMinus2, "density");
+                   Unit::nanometerMinus2, 5, 0.0001, RealLimits::nonnegative(), "density");
 }
 
 std::unique_ptr<IInterference> InterferenceHardDiskItem::createInterference() const
diff --git a/GUI/Model/Sample/ParticleLayoutItem.cpp b/GUI/Model/Sample/ParticleLayoutItem.cpp
index ee630d166e8d1f0295e937275497c886800fe89c..a92f0cdaef67e15aafb37a80753d20bf006c152c 100644
--- a/GUI/Model/Sample/ParticleLayoutItem.cpp
+++ b/GUI/Model/Sample/ParticleLayoutItem.cpp
@@ -37,7 +37,7 @@ ParticleLayoutItem::ParticleLayoutItem(const MaterialItems* materials)
     m_ownDensity.init("Total particle density",
                       "Number of particles per area (particle surface density).\n "
                       "Should be defined for disordered and 1d-ordered particle collections.",
-                      0.0005, Unit::nanometerMinus2, 10, RealLimits::nonnegative(), "density");
+                      0.0005, Unit::nanometerMinus2, 10, 0.0001, RealLimits::nonnegative(), "density");
 
     m_interference.init<InterferenceItemCatalog>("Interference function", "", "interference");
 }