diff --git a/Cargo.lock b/Cargo.lock
index 9f58f0c..4258b50 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1517,6 +1517,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "md5"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "490cc448043f947bae3cbee9c203358d62dbee0db12107a74be5c30ccfd09771"
+
 [[package]]
 name = "memchr"
 version = "2.5.0"
@@ -2026,6 +2032,7 @@ dependencies = [
  "flate2",
  "gd_plist",
  "home",
+ "md5",
  "ordered-float",
  "reqwest",
  "rodio",
diff --git a/Cargo.toml b/Cargo.toml
index cbabc06..e8a1004 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -17,3 +17,4 @@ ordered-float = "3.4.0"
 thiserror = "1.0.38"
 reqwest = {version = "0.11.14", features = [ "blocking" ]}
 urlencoding = "2.1.2"
+md5 = "0.7.0"
diff --git a/src/gd.rs b/src/gd.rs
index 40faf0d..fed47f8 100644
--- a/src/gd.rs
+++ b/src/gd.rs
@@ -29,25 +29,27 @@ struct Level {
     song: Song,
 }
 
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 pub struct OuterLevel {
     name: String,          // k2
     revision: Option<i64>, // k46
 }
 
-#[derive(Debug, Error, Clone)]
+pub struct InnerLevel(String);
+
+#[derive(Debug, Error)]
 pub enum SongRequestError {
     #[error("Request failed")]
-    ConnectionFailure,
+    ConnectionFailure(#[from] reqwest::Error),
     #[error("Index is not an int?????")]
     ParseFailure(#[from] ParseIntError),
     #[error("Not a Newgrounds song")]
     NotNewgrounds,
 }
 
-impl From<reqwest::Error> for SongRequestError {
-    fn from(_: reqwest::Error) -> Self {
-        Self::ConnectionFailure
+impl InnerLevel {
+    pub fn try_from_encoded_ils(ils: &str) -> Option<Self> {
+        todo!()
     }
 }
 
@@ -108,8 +110,7 @@ impl SongResponse {
 
 impl OuterLevel {
     pub fn load_all() -> Vec<Self> {
-        let plist = get_local_level_plist();
-        let levels: Vec<Self> = plist
+        get_local_level_plist()
             .as_dictionary()
             .and_then(|dict| dict.get("LLM_01"))
             .unwrap()
@@ -128,8 +129,31 @@ impl OuterLevel {
                 }
                 builder.build_outer_level().unwrap()
             })
-            .collect();
-        levels
+            .collect()
+    }
+
+    pub fn load_inner(&self) -> InnerLevel {
+        get_local_level_plist()
+            .as_dictionary()
+            .and_then(|dict| dict.get("LLM_01"))
+            .unwrap()
+            .as_dictionary()
+            .unwrap()
+            .iter()
+            .find(|(key, val)| key.as_str() != "_isArr" && {
+                let props = val.as_dictionary().unwrap();
+                props.get("k2").unwrap().as_string().unwrap() == self.name
+                    && props.get("k46").and_then(|rev| rev.as_signed_integer()) == self.revision
+            })
+            .unwrap()
+            .1
+            .as_dictionary()
+            .unwrap()
+            .get("k4")
+            .unwrap()
+            .as_string()
+            .and_then(|str| InnerLevel::try_from_encoded_ils(str))
+            .unwrap()
     }
 
     pub fn display_name(&self) -> LayoutJob {
diff --git a/src/main.rs b/src/main.rs
index 9189fad..20f835a 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,5 +1,6 @@
 #![feature(iter_array_chunks)]
-//#![warn(clippy::all, clippy::pedantic, clippy::nursery)]
+#![warn(clippy::all, clippy::pedantic, clippy::nursery)]
+#![allow(dead_code)]
 
 mod gd;
 mod music;
@@ -11,13 +12,17 @@ use std::collections::VecDeque;
 use std::fs::File;
 use std::io::Write;
 use thiserror::Error;
+use std::error::Error;
+use std::mem;
 
 struct PipeDash {
     msg_queue: VecDeque<Message>,
     selected_level: Option<usize>,
     level_list: Vec<gd::OuterLevel>,
     loaded_song: Option<Song>,
+    loaded_level_checksum: Option<(gd::OuterLevel, md5::Digest)>,
     editor: Editor,
+    error: Option<Box<dyn Error>>
 }
 
 #[derive(Debug, PartialEq, Eq)]
@@ -30,6 +35,8 @@ enum Color {
 #[derive(Debug)]
 enum Message {
     LevelSelected(usize),
+    CloseError,
+    LoadLevel,
 }
 
 struct Editor {
@@ -252,6 +259,8 @@ impl PipeDash {
             msg_queue: VecDeque::new(),
             level_list: gd::OuterLevel::load_all(),
             loaded_song: None,
+            loaded_level_checksum: None,
+            error: None,
             editor: Editor {
                 state: EditorState {
                     scroll_pos: 0f32,
@@ -274,7 +283,9 @@ impl PipeDash {
             .default_width(100f32)
             .show(ctx, |ui| {
                 ui.with_layout(egui::Layout::top_down(egui::Align::LEFT), |ui| {
-                    ui.button("Load Level");
+                    if ui.add_enabled(self.selected_level.is_some(), egui::Button::new("Load Level")).clicked() {
+                        self.msg_queue.push_back(Message::LoadLevel);
+                    }
                     egui::ScrollArea::vertical().show(ui, |ui| {
                         ui.with_layout(egui::Layout::top_down_justified(egui::Align::Min), |ui| {
                             for (idx, level) in self.level_list.iter().enumerate() {
@@ -324,14 +335,27 @@ impl PipeDash {
         });
     }
 
+    fn handle_message(&mut self, message: Message) {
+        match message {
+            Message::LevelSelected(idx) => self.selected_level = Some(idx),
+            Message::CloseError => self.error = None,
+            Message::LoadLevel => {
+                // Load song & GdlData
+                let level = self.selected_level
+                    .and_then(|idx| self.level_list.get(idx))
+                    .unwrap()  // will not panic. selected_level range is same as level_list...
+                    .clone();  // ...length - 1; message will not be sent if selected_level is none
+
+                todo!();
+            },
+        }
+
+    }
+
     fn handle_messages(&mut self) {
-        for message in self.msg_queue.drain(..) {
+        for message in mem::take(&mut self.msg_queue) {
             println!("{message:?}");
-            match message {
-                Message::LevelSelected(idx) => {
-                    self.selected_level = Some(idx);
-                }
-            }
+            self.handle_message(message);
         }
     }
 }
@@ -340,8 +364,17 @@ impl eframe::App for PipeDash {
     fn update(&mut self, ctx: &egui::Context, frame: &mut eframe::Frame) {
         ctx.set_pixels_per_point(2f32);
 
-        self.side_panel(ctx, frame);
-        self.center_panel(ctx, frame);
+        if let Some(boxed_err) = &self.error {
+            egui::CentralPanel::default().show(ctx, |ui| {
+                ui.label(boxed_err.to_string());
+                if ui.button("Close").clicked() {
+                    self.msg_queue.push_back(Message::CloseError);
+                }
+            });
+        } else {
+            self.side_panel(ctx, frame);
+            self.center_panel(ctx, frame);
+        }
 
         self.handle_messages();
     }