Fix mapgen selection problem and whitespaces(?)

builtin/mainmenu/dlg_create_world.lua

@@ -87,11 +87,6 @@ local function create_world_formspec(dialogdata)
 		mapgens[#mapgens+1] = k
 	end
 
-	local current_mapgen_internal = dialogdata.mg
-	if lua_mapgens[current_mapgen_internal] then
-		current_mapgen_internal = "singlenode"
-	end
-
 	local flags = dialogdata.flags
 
 	local game = pkgmgr.find_by_gameid(core.settings:get("menu_last_game"))
@@ -159,6 +154,11 @@ local function create_world_formspec(dialogdata)
 		mglist = mglist:sub(1, -2)
 	end
 
+	local current_mapgen_internal = current_mapgen
+	if lua_mapgens[current_mapgen_internal] and current_mapgen == dialogdata.mg then
+		current_mapgen_internal = "singlenode"
+	end
+
 	-- The logic of the flag element IDs is as follows:
 	-- "flag_main_foo-bar-baz" controls dialogdata.flags["main"]["foo_bar_baz"]
 	-- see the buttonhandler for the implementation of this

mapgens/egen/init.lua

@@ -0,0 +1 @@
+print("Loaded Egen!")

mapgens/egen/mapgen.conf

@@ -0,0 +1,5 @@
+name = egen
+title = Egen
+description = Example mapgen.
+author = TX_Miner/Xeno333
+mapgen = true