diff --git a/examples/generate/external/layout.yaml b/examples/generate/external/layout.yaml
index 05a58ca..e7e23cf 100644
--- a/examples/generate/external/layout.yaml
+++ b/examples/generate/external/layout.yaml
@@ -4,15 +4,23 @@ blocks:
     x: 17.0
     y: -157.0
     orientation: normal
+    width: 120.0
+    height: 60.0
   error:
     x: 196.0
     y: -149.0
     orientation: normal
+    width: 120.0
+    height: 60.0
   pid:
     x: 369.0
     y: -149.0
     orientation: normal
+    width: 120.0
+    height: 60.0
   plant:
     x: 530.0
     y: -150.0
     orientation: normal
+    width: 120.0
+    height: 60.0
diff --git a/pySimBlocks/gui/dialogs/settings/project.py b/pySimBlocks/gui/dialogs/settings/project.py
index eaf1c31..bd2335e 100644
--- a/pySimBlocks/gui/dialogs/settings/project.py
+++ b/pySimBlocks/gui/dialogs/settings/project.py
@@ -19,8 +19,9 @@
 # ******************************************************************************
 
 from pathlib import Path
+import os
 from PySide6.QtWidgets import (
-    QWidget, QFormLayout, QLabel, QLineEdit, QMessageBox, QPushButton, QComboBox
+    QWidget, QFormLayout, QLabel, QLineEdit, QMessageBox, QPushButton, QFileDialog, QHBoxLayout
 )
 
 from pySimBlocks.gui.model.project_state import ProjectState
@@ -40,7 +41,16 @@ def __init__(self, project_state: ProjectState, project_controller: ProjectContr
         layout.addRow(QLabel("<b>Project Settings</b>"))
 
         self.dir_edit = QLineEdit(str(project_state.directory_path))
-        layout.addRow("Directory path:", self.dir_edit)
+        self.dir_browse_btn = QPushButton("...")
+        self.dir_browse_btn.setToolTip("Select a project directory from disk")
+        self.dir_browse_btn.clicked.connect(self.browse_project_directory)
+
+        dir_layout = QHBoxLayout()
+        dir_layout.setContentsMargins(0, 0, 0, 0)
+        dir_layout.addWidget(self.dir_edit)
+        dir_layout.addWidget(self.dir_browse_btn)
+
+        layout.addRow("Directory path:", dir_layout)
 
         load_btn = QPushButton("Load")
         load_btn.clicked.connect(self.load_project)
@@ -50,9 +60,18 @@ def __init__(self, project_state: ProjectState, project_controller: ProjectContr
 
         ext = project_state.external or ""
         self.external_edit = QLineEdit(ext)
+        self.external_browse_btn = QPushButton("...")
+        self.external_browse_btn.setToolTip("Select a Python file from disk")
+        self.external_browse_btn.clicked.connect(self.browse_external_file)
+
+        external_layout = QHBoxLayout()
+        external_layout.setContentsMargins(0, 0, 0, 0)
+        external_layout.addWidget(self.external_edit)
+        external_layout.addWidget(self.external_browse_btn)
+
         label = QLabel("Python file:")
         label.setToolTip("Relative path from project directory")
-        layout.addRow(label, self.external_edit)
+        layout.addRow(label, external_layout)
 
 
 
@@ -69,6 +88,49 @@ def apply(self) -> bool:
         self.project_controller.update_project_param(path, ext)
         return True
 
+    def browse_external_file(self):
+        base_dir = Path(self.dir_edit.text()).expanduser()
+        if not base_dir.is_dir():
+            QMessageBox.warning(
+                self,
+                "Invalid directory",
+                f"The directory does not exist:\n{base_dir}",
+            )
+            return
+
+        selected_file, _ = QFileDialog.getOpenFileName(
+            self,
+            "Select Python file",
+            str(base_dir),
+            "Python files (*.py);;All files (*)",
+        )
+
+        if not selected_file:
+            return
+
+        selected_path = Path(selected_file).resolve()
+        try:
+            relative_path = selected_path.relative_to(base_dir.resolve())
+        except ValueError:
+            relative_path = Path(os.path.relpath(str(selected_path), str(base_dir.resolve())))
+
+        self.external_edit.setText(str(relative_path))
+
+    def browse_project_directory(self):
+        current_dir = Path(self.dir_edit.text()).expanduser()
+        start_dir = current_dir if current_dir.is_dir() else Path.cwd()
+
+        selected_dir = QFileDialog.getExistingDirectory(
+            self,
+            "Select project directory",
+            str(start_dir),
+        )
+
+        if not selected_dir:
+            return
+
+        self.dir_edit.setText(str(Path(selected_dir).resolve()))
+
     def load_project(self):
         self.apply()
         self.project_controller.load_project(ProjectLoaderYaml())
diff --git a/pyproject.toml b/pyproject.toml
index b940645..f782675 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -39,6 +39,7 @@ pySimBlocks = [
 [project.optional-dependencies]
 examples = [
     "control",
+    "qpsolvers[osqp,clarabel]",
 ]
 
 tests = [
diff --git a/requirements.txt b/requirements.txt
deleted file mode 100644
index 7bc36ca..0000000
--- a/requirements.txt
+++ /dev/null
@@ -1,47 +0,0 @@
-altair==6.0.0
-attrs==25.4.0
-blinker==1.9.0
-cachetools==6.2.2
-certifi==2025.11.12
-charset-normalizer==3.4.4
-click==8.3.1
-contourpy==1.3.2
-control==0.10.2
-cycler==0.12.1
-fonttools==4.61.0
-gitdb==4.0.12
-GitPython==3.1.45
-graphviz==0.21
-idna==3.11
-Jinja2==3.1.6
-jsonschema==4.25.1
-jsonschema-specifications==2025.9.1
-kiwisolver==1.4.9
-MarkupSafe==3.0.3
-matplotlib==3.10.7
-narwhals==2.13.0
-numpy==2.2.6
-packaging==25.0
-pandas==2.3.3
-pillow==12.0.0
-protobuf==6.33.1
-pyarrow==22.0.0
-pydeck==0.9.1
-pyparsing==3.2.5
-python-dateutil==2.9.0.post0
-pytz==2025.2
-PyYAML==6.0.3
-referencing==0.37.0
-requests==2.32.5
-rpds-py==0.30.0
-scipy==1.15.3
-six==1.17.0
-smmap==5.0.2
-streamlit==1.52.0
-tenacity==9.1.2
-toml==0.10.2
-tornado==6.5.2
-typing_extensions==4.15.0
-tzdata==2025.2
-urllib3==2.5.0
-watchdog==6.0.0