diff --git a/alt-tab-macos/logic/Keyboard.swift b/alt-tab-macos/logic/Keyboard.swift
index b354283b..1ca60332 100644
--- a/alt-tab-macos/logic/Keyboard.swift
+++ b/alt-tab-macos/logic/Keyboard.swift
@@ -2,10 +2,10 @@ import Cocoa
 
 // Apple doesn't provide an enum for this, strangely
 enum KeyCode: UInt16 {
+    case tab = 48
     case escape = 53
     case command = 55
     case capsLock = 57
-    case tab = 58
     case control = 59
     case function = 63
     case leftArrow = 123
diff --git a/alt-tab-macos/logic/Preferences.swift b/alt-tab-macos/logic/Preferences.swift
index f32bc2aa..6862711c 100644
--- a/alt-tab-macos/logic/Preferences.swift
+++ b/alt-tab-macos/logic/Preferences.swift
@@ -3,12 +3,12 @@ import Cocoa
 
 class Preferences {
     static var defaults: [String: String] = [
-        "version": "1", // bump this anytime the dictionary is changed
-        "maxScreenUsage": "0.8",
+        "version": "2", // bump this anytime the dictionary is changed
+        "maxScreenUsage": "80",
         "maxThumbnailsPerRow": "4",
         "iconSize": "32",
         "fontHeight": "15",
-        "tabKey": String(KeyCode.tab.rawValue),
+        "tabKeyCode": String(KeyCode.tab.rawValue),
         "metaKey": metaKeyMacro.macros[0].label,
         "windowDisplayDelay": "0",
         "theme": themeMacro.macros[0].label
@@ -67,7 +67,7 @@ class Preferences {
     static func updateAndValidateFromString(_ valueName: String, _ value: String) throws {
         switch valueName {
         case "maxScreenUsage":
-            maxScreenUsage = try CGFloat(value).orThrow()
+            maxScreenUsage = try CGFloat(CGFloat(value).orThrow() / 100)
         case "maxThumbnailsPerRow":
             maxThumbnailsPerRow = try CGFloat(value).orThrow()
         case "iconSize":
@@ -75,7 +75,7 @@ class Preferences {
         case "fontHeight":
             fontHeight = try CGFloat(value).orThrow()
             font = NSFont.systemFont(ofSize: fontHeight!)
-        case "tabKey":
+        case "tabKeyCode":
             tabKeyCode = try UInt16(value).orThrow()
         case "metaKey":
             let p = try metaKeyMacro.labelToMacro[value].orThrow()
diff --git a/alt-tab-macos/ui/PreferencesPanel.swift b/alt-tab-macos/ui/PreferencesPanel.swift
index 033642e7..8a977f58 100644
--- a/alt-tab-macos/ui/PreferencesPanel.swift
+++ b/alt-tab-macos/ui/PreferencesPanel.swift
@@ -11,7 +11,7 @@ class PreferencesPanel: NSPanel, NSTextViewDelegate {
     var iconSize: NSTextView?
     var fontHeight: NSTextView?
     var interItemPadding: NSTextView?
-    var tabKey: NSTextView?
+    var tabKeyCode: NSTextView?
     var windowDisplayDelay: NSTextView?
     var metaKey: NSPopUpButton?
     var theme: NSPopUpButton?
@@ -28,7 +28,7 @@ class PreferencesPanel: NSPanel, NSTextViewDelegate {
         [
             makeLabelWithDropdown(\PreferencesPanel.theme, "Main window theme", "theme", Preferences.themeMacro.labels),
             makeLabelWithDropdown(\PreferencesPanel.metaKey, "Meta key to activate the app", "metaKey", Preferences.metaKeyMacro.labels),
-            makeLabelWithInput(\PreferencesPanel.tabKey, "Tab key (NSEvent.keyCode)", "tabKey"),
+            makeLabelWithInput(\PreferencesPanel.tabKeyCode, "Tab key (NSEvent.keyCode)", "tabKeyCode"),
             makeLabelWithInput(\PreferencesPanel.maxScreenUsage, "Max window size (screen %)", "maxScreenUsage"),
             makeLabelWithInput(\PreferencesPanel.maxThumbnailsPerRow, "Max thumbnails per row", "maxThumbnailsPerRow"),
             makeLabelWithInput(\PreferencesPanel.iconSize, "Apps icon size (px)", "iconSize"),