diff --git a/src/main/java/ru/dbotthepony/kstarbound/lua/LuaJNR.java b/src/main/java/ru/dbotthepony/kstarbound/lua/LuaJNR.java
index 2f167325..417cdcb2 100644
--- a/src/main/java/ru/dbotthepony/kstarbound/lua/LuaJNR.java
+++ b/src/main/java/ru/dbotthepony/kstarbound/lua/LuaJNR.java
@@ -7,8 +7,7 @@ import jnr.ffi.Runtime;
 import jnr.ffi.annotations.IgnoreError;
 import jnr.ffi.annotations.LongLong;
 import org.jetbrains.annotations.NotNull;
-
-import javax.annotation.Nullable;
+import org.jetbrains.annotations.Nullable;
 
 @SuppressWarnings({"UnnecessaryModifier", "SpellCheckingInspection", "unused"})
 public interface LuaJNR {
@@ -34,7 +33,7 @@ public interface LuaJNR {
 	@IgnoreError
 	public long lua_atpanic(@NotNull Pointer luaState, @LongLong long fn);
 	@IgnoreError
-	public long luaL_traceback(@NotNull Pointer luaState, @NotNull Pointer forState, @NotNull String message, int level);
+	public long luaL_traceback(@NotNull Pointer luaState, @NotNull Pointer forState, @Nullable String message, int level);
 
 	/**
 	 * Creates a new thread, pushes it on the stack, and returns a pointer to a lua_State that represents this new thread. The new thread returned by this function shares with the original thread its global environment, but has an independent execution stack.
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/lua/LuaSharedState.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/lua/LuaSharedState.kt
index e29f7f9f..161c0705 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/lua/LuaSharedState.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/lua/LuaSharedState.kt
@@ -71,15 +71,13 @@ class LuaSharedState(val handlesThread: LuaThread, private val cleanable: Cleana
 			val peek = it.peek()
 
 			if (peek == LuaType.STRING) {
-				it.lua.traceback(it.lua.getString()!!, 1)
-				val err = LuaRuntimeException(it.lua.getString())
+				val err = LuaRuntimeException(it.lua.traceback(it.lua.getString(), 1))
 				it.lua.push(err)
 			} else if (peek == LuaType.USERDATA) {
 				val obj = it.nextObject<Any>()
 
 				if (obj is Throwable && obj !is LuaRuntimeException) {
-					it.lua.traceback(obj.toString(), 1)
-					val err = LuaRuntimeException(it.lua.getString(), cause = obj, writeStackTrace = false)
+					val err = LuaRuntimeException(it.lua.traceback(obj.toString(), 1), cause = obj, writeStackTrace = false)
 					it.lua.push(err)
 				}
 			}
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/lua/LuaThread.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/lua/LuaThread.kt
index 9e17ee37..b8c59b79 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/lua/LuaThread.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/lua/LuaThread.kt
@@ -340,8 +340,9 @@ class LuaThread private constructor(
 		return callConditional(numResults, { block(this); true })!!
 	}
 
-	fun traceback(message: String, level: Int = 0) {
+	fun traceback(message: String? = null, level: Int = 0): String {
 		LuaJNR.INSTANCE.luaL_traceback(pointer, pointer, message, level)
+		return popString()!!
 	}
 
 	fun invokeGlobal(name: String): Boolean {
@@ -1212,10 +1213,13 @@ class LuaThread private constructor(
 
 		fun nextBoolean(position: Int = this.position++): Boolean {
 			if (position !in 1 ..this.top)
-				throw IllegalArgumentException("bad argument #$position: boolean expected, got nil")
+				return false
 
-			return this@LuaThread.getBoolean(position)
-				?: throw IllegalArgumentException("bad argument #$position: boolean expected, got ${this@LuaThread.typeAt(position)}")
+			return when (typeAt(position)) {
+				LuaType.NONE, LuaType.NIL -> false
+				LuaType.BOOLEAN -> this@LuaThread.getBooleanRaw(position)
+				else -> true
+			}
 		}
 	}
 
@@ -1665,8 +1669,18 @@ class LuaThread private constructor(
 					val num = value.asNumber
 
 					when (num) {
-						is Int, is Long -> this.push(num.toLong())
-						else -> this.push(num.toDouble())
+						is Int, is Long -> push(num.toLong())
+						is Float, is Double -> push(num.toDouble())
+						else -> {
+							// lazy parsed number
+							val str = value.asString
+
+							if (str.none { it == '.' } || str.endsWith(".0")) {
+								push(num.toLong())
+							} else {
+								push(num.toDouble())
+							}
+						}
 					}
 				} else if (value.isString) {
 					this.push(value.asString)
@@ -1711,7 +1725,8 @@ class LuaThread private constructor(
 	}
 
 	override fun toString(): String {
-		return "LuaThread at ${pointer.address()}"
+		val p = pointer.address().toString(16)
+		return "LuaThread at 0x${if (p.length < 12) "0".repeat(12 - p.length) else ""}${p}"
 	}
 
 	companion object {