diff --git a/macros/l0.DependencyControl.Toolbox.moon b/macros/l0.DependencyControl.Toolbox.moon
index 3c7b2f6..fd43203 100644
--- a/macros/l0.DependencyControl.Toolbox.moon
+++ b/macros/l0.DependencyControl.Toolbox.moon
@@ -26,6 +26,10 @@ logger.usePrefixWindow = false
 msgs = {
   install: {
     scanning: "Scanning %d available feeds...",
+    scanningTask: "Scanning available feeds..."
+    loadingTask: "Loading feed data..."
+    empty: "All available scripts are already installed."
+    emptyUnfetched: "No scripts are available to install (%d of %d known feeds could not be fetched)."
     createScriptUpdateRecordFailed: "Failed to create an update record for %s '%s' from feed %s: %s"
   }
   uninstall: {
@@ -218,11 +222,16 @@ promptUntrustedFeed = (url, ft) ->
 
 -- Crawls the feed inventory with the untrusted-feed prompter active (so the `prompt` policy asks), scoped
 -- so the prompter never leaks into background fetches. Shared by install discovery and Manage Feeds.
-crawlWithPrompt = (inventory) ->
+-- The pcall keeps a cancellation raised from onProgress from skipping the prompter reset;
+-- returns nil when the crawl was cancelled and re-raises anything else.
+crawlWithPrompt = (inventory, onProgress) ->
   feedTrust = DepCtrl.updater.feedTrust
   feedTrust\setPrompter promptUntrustedFeed
-  entries = inventory\crawl!
+  ok, entries = pcall inventory.crawl, inventory, onProgress
   feedTrust\setPrompter nil
+  if not ok and entries != "cancelled"
+    error entries, 0
+  return nil unless ok
   entries
 
 -- Macros
@@ -261,8 +270,14 @@ install = ->
   -- FeedInventory crawls the known feeds, which are trust-gated and bounded. The shared feed loader then
   -- serves each reachable feed's data from the cache the crawl just populated.
   macros, modules = {}, {}
-  entries = crawlWithPrompt buildFeedInventory!
-
+  aegisub.progress.task msgs.install.scanningTask
+  entries = crawlWithPrompt buildFeedInventory!, (fetched, known) ->
+    aegisub.progress.set math.floor fetched * 100 / known
+    error "cancelled", 0 if aegisub.progress.is_cancelled!
+  aegisub.progress.set 100
+  return unless entries
+
+  aegisub.progress.task msgs.install.loadingTask
   logger\log msgs.install.scanning, #entries
   for entry in *entries
     continue unless entry.fetched
@@ -273,6 +288,13 @@ install = ->
   moduleList, moduleMap = buildDlgList modules
   macroList, macroMap = buildDlgList macros
 
+  if #moduleList == 0 and #macroList == 0
+    unfetched = #[entry for entry in *entries when not entry.fetched]
+    message = unfetched > 0 and msgs.install.emptyUnfetched\format(unfetched, #entries) or msgs.install.empty
+    aegisub.dialog.display {{class: "label", x: 0, y: 0, width: 1, height: 1, label: message}},
+      {buttons.close}, {ok: buttons.close, cancel: buttons.close}
+    return
+
   btn, res = aegisub.dialog.display getScriptListDlg macroList, moduleList
   return unless btn
 
diff --git a/modules/l0/DependencyControl/FeedInventory.moon b/modules/l0/DependencyControl/FeedInventory.moon
index b04ba76..912f141 100644
--- a/modules/l0/DependencyControl/FeedInventory.moon
+++ b/modules/l0/DependencyControl/FeedInventory.moon
@@ -242,11 +242,12 @@ class FeedInventory
 
   ---Fetches feeds and discovers transitively-advertised ones by crawling the `knownFeeds` graph out from the
   ---config-derived feeds; untrusted expansion is bounded, so check `stats.truncated` for incomplete results.
+  ---@param onProgress? fun(fetched: integer, known: integer) Called after each feed is fetched, with the running fetch count and the number of feeds currently known to the crawl (more are discovered as it goes, so `known` may grow).
   ---@return FeedInventoryEntry[] feeds The known feeds, enriched with what the crawl discovered.
   ---@return FeedCrawlStats stats What the crawl explored and where it stopped short.
-  crawl: =>
+  crawl: (onProgress) =>
     inventoryEntriesByUrl = @__collectConfigFeeds!
-    stats = @__crawlKnownFeeds inventoryEntriesByUrl
+    stats = @__crawlKnownFeeds inventoryEntriesByUrl, onProgress
     return @__finalize(inventoryEntriesByUrl), stats
 
   ---Breadth-first crawl of the `knownFeeds` graph, extending inventoryEntriesByUrl in place with the transitively-discovered
@@ -254,8 +255,9 @@ class FeedInventory
   ---malicious subtree can't starve the others.
   ---@private
   ---@param inventoryEntriesByUrl table<string, FeedInventoryEntry> The config-derived feeds to start from; extended in place.
+  ---@param onProgress? fun(fetched: integer, known: integer) Called after each feed is fetched (see `crawl`).
   ---@return FeedCrawlStats stats
-  __crawlKnownFeeds: (inventoryEntriesByUrl) =>
+  __crawlKnownFeeds: (inventoryEntriesByUrl, onProgress) =>
     c = @config.c
     limits = c.feeds.crawlLimits or {}
     defaults = @@defaultCrawlLimits
@@ -300,6 +302,7 @@ class FeedInventory
       continue unless knownFeeds
       stats.fetched += 1
       inventoryEntriesByUrl[feedUrl].fetched = true
+      onProgress stats.fetched, #queue - head + 1 + stats.fetched if onProgress
 
       perFeedUntrusted = 0
       perFeedDrops, perRootDrops = newDrops!, newDrops!