diff --git a/advtrains/trackplacer.lua b/advtrains/trackplacer.lua
index ffae736..258c9cd 100644
--- a/advtrains/trackplacer.lua
+++ b/advtrains/trackplacer.lua
@@ -207,15 +207,18 @@ function tp.placetrack(pos, nnpref, placer, itemstack, pointed_thing, yaw)
 					if (dconn1[conn1.."_"..conn2]) then
 						using = dconn1[conn1.."_"..conn2]
 					end
-					
-					tp.bend_rail(p_railpos[conn1], conn1, nnpref)
-					tp.bend_rail(p_railpos[conn2], conn2, nnpref)
-					advtrains.ndb.swap_node(pos, using)
-					local nname=using.name
-					if minetest.registered_nodes[nname] and minetest.registered_nodes[nname].after_place_node then
-						minetest.registered_nodes[nname].after_place_node(pos, placer, itemstack, pointed_thing)
+					if using then
+						-- has found a fitting rail in either direction
+						-- if not, continue loop
+						tp.bend_rail(p_railpos[conn1], conn1, nnpref)
+						tp.bend_rail(p_railpos[conn2], conn2, nnpref)
+						advtrains.ndb.swap_node(pos, using)
+						local nname=using.name
+						if minetest.registered_nodes[nname] and minetest.registered_nodes[nname].after_place_node then
+							minetest.registered_nodes[nname].after_place_node(pos, placer, itemstack, pointed_thing)
+						end
+						return
 					end
-					return
 				end
 			end
 		end
diff --git a/advtrains_luaautomation/active_common.lua b/advtrains_luaautomation/active_common.lua
index 62dc83c..d4cc0da 100644
--- a/advtrains_luaautomation/active_common.lua
+++ b/advtrains_luaautomation/active_common.lua
@@ -118,7 +118,7 @@ function ac.run_in_env(pos, evtdata, customfct_p)
 		atlatc.interrupt.add(t, pos, {type="int", int=true, message=imesg})
 	end
 	-- add digiline_send function, if digiline is loaded
-	if digiline then
+	if minetest.global_exists("digiline") then
 		customfct.digiline_send=function(channel, msg)
 			assertt(channel, "string")
 			digiline:receptor_send(pos, digiline.rules.default, channel, msg)