diff --git a/ports/boom.lua b/ports/boom.lua
index a92688c84..e8aacb95d 100644
--- a/ports/boom.lua
+++ b/ports/boom.lua
@@ -147,7 +147,7 @@ OB_PORTS["boom"] =
 {
   label = _("BOOM Compat"),
 
-  priority = 98,  -- this makes it top-most, and the default engine
+  priority = 102,  -- this makes it top-most, and the default engine
 
   game = { chex1=0, doom1=1, doom2=1, hacx=0, harmony=0, strife=0, rekkr=0 },
 
diff --git a/ports/edge.lua b/ports/edge.lua
index 216338451..feb366e90 100644
--- a/ports/edge.lua
+++ b/ports/edge.lua
@@ -159,7 +159,7 @@ OB_PORTS["edge"] =
 
   extends = "advanced",
 
-  priority = 95,
+  priority = 99,
 
   game = { chex1=0, doom1=1, doom2=1, hacx=0, harmony=0, heretic=1, ultdoom=1, tnt=1, plutonia=1, strife=0, rekkr=0 },
 
diff --git a/ports/vanilla.lua b/ports/vanilla.lua
index 6ed73dda5..c71de693d 100644
--- a/ports/vanilla.lua
+++ b/ports/vanilla.lua
@@ -41,7 +41,7 @@ OB_PORTS["vanilla"] =
 {
   label = _("Vanilla"),
 
-  priority = 100,
+  priority = 101,
 
   engine = {idtech_0=1,idtech_1=0},
 
diff --git a/ports/zdoom.lua b/ports/zdoom.lua
index 4326fea61..8c264757f 100644
--- a/ports/zdoom.lua
+++ b/ports/zdoom.lua
@@ -60,7 +60,7 @@ end
 OB_PORTS["zdoom"] =
 {
   label = _("GZDoom"),
-  priority = 101,
+  priority = 100,
 
   extends = "advanced",
 
diff --git a/scripts/obsidian.lua b/scripts/obsidian.lua
index 11a7622bd..28c965dc4 100644
--- a/scripts/obsidian.lua
+++ b/scripts/obsidian.lua
@@ -181,9 +181,6 @@ function ob_match_engine(T)
   local engine = T.engine
   local result = true
 
-  -- Compatibility stub for old "gzdoom" selection
-  if engine == "gzdoom" then engine = "zdoom" end
-
   -- negated check?
   if type(engine) == "string" and string.sub(engine, 1, 1) == '!' then
     engine = string.sub(engine, 2)
@@ -572,7 +569,7 @@ function ob_update_ports()
       if OB_CONFIG.game == "chex1" or OB_CONFIG.game == "hacx" or OB_CONFIG.game == "harmony" or OB_CONFIG.game == "strife" or OB_CONFIG.game == "rekkr" then  -- Ugh
         OB_CONFIG.port = "limit_enforcing"
       else
-        OB_CONFIG.port = "zdoom"
+        OB_CONFIG.port = "boom"
       end
     else -- shouldn't get here - Dasho
       OB_CONFIG.port = "vanilla"
@@ -2407,7 +2404,7 @@ local function ob_get_module_refs()
         "zdoom",
         "edge",
       },
-      default = "zdoom",
+      default = "boom",
     },
     length = {
       tooltip = _("Choose how many levels to create."),
diff --git a/theme/zdoom_forums.txt b/theme/zdoom_forums.txt
index 8d399212d..a574df507 100644
--- a/theme/zdoom_forums.txt
+++ b/theme/zdoom_forums.txt
@@ -1,5 +1,7 @@
--- ZDoom Forums theme by Cubebert
-
+-- THEME FILE : OBSIDIAN 21 "Unstable"
+-- Build 2024.05.24
+-- Based on OBLIGE Level Maker (C) 2006-2017 Andrew Apted
+-- https://obsidian-level-maker.github.io
 
 window_scaling      = 0                                                 
 font_scaling      = 20                                                
@@ -7,8 +9,6 @@ font_theme      = 1
 widget_theme      = 0                                                 
 box_theme      = 0                                                 
 button_theme      = 0                                                 
-single_pane = 0                                                 
-use_system_fonts = 0                                                 
 color_scheme      = 1                                                 
 text_red      = 95                                                
 text_green      = 81