diff --git a/source/tools/rmgen/api.cpp b/source/tools/rmgen/api.cpp
index fc4e2bc320..fb414c19dc 100644
--- a/source/tools/rmgen/api.cpp
+++ b/source/tools/rmgen/api.cpp
@@ -23,8 +23,8 @@ JSFunctionSpec globalFunctions[] = {
 	{"getHeight", getHeight, 2},
 	{"setHeight", setHeight, 3},
 	{"getMapSize", getMapSize, 0},
-	{"randInt", randInt, 1},
-	{"randFloat", randFloat, 0},
+	{"randInt", randInt, 2},
+	{"randFloat", randFloat, 1},
 	{"placeObject", placeObject, 4},
 	{"createArea", createArea, 3},
 	{"createObjectGroup", createObjectGroup, 3},
@@ -38,7 +38,7 @@ JSFunctionSpec globalFunctions[] = {
 void ValidateArgs(const char* types, JSContext* cx, uintN argc, jsval* argv, const char* function) {
 	int num = strlen(types);
 	if(argc != num) {
-		JS_ReportError(cx, "%s: expected %d arguments but got %d", function, num, argc);
+		JS_ReportError(cx, "%s: requires %d arguments but got %d", function, num, argc);
 	}
 	JSObject* obj;
 	for(int i=0; i<num; i++) {
@@ -189,22 +189,57 @@ JSBool setHeight(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *r
 
 JSBool randInt(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
 {
-	ValidateArgs("i", cx, argc, argv, __FUNCTION__);
-	
-	int x = JSVAL_TO_INT(argv[0]);
-	if(x<=0) {
-		JS_ReportError(cx, "randInt: argument must be positive");
+	if(argc!=1 && argc!=2) {
+		JS_ReportError(cx, "randInt: requires 1 or 2 arguments but got %d", argc);
 	}
-	int r = RandInt(x);
+	if(!JSVAL_IS_INT(argv[0])) {
+		JS_ReportError(cx, "randInt: argument 1 must be an integer");
+	}
+	if(argc==2 && !JSVAL_IS_INT(argv[1])) {
+		JS_ReportError(cx, "randInt: argument 2 must be an integer");
+	}
+	
+	int minVal = argc==1 ? 0 : JSVAL_TO_INT(argv[0]);
+	int maxVal = argc==1 ? JSVAL_TO_INT(argv[0]) : JSVAL_TO_INT(argv[1])-1;
+	if(maxVal < minVal) {
+		JS_ReportError(cx, argc==1 ? "randInt: argument must be positive" 
+								   : "randInt: argument 2 must be greater than or equal to argument 1");
+	}
+	int r = RandInt(minVal, maxVal);
 	*rval = INT_TO_JSVAL(r);
 	return JS_TRUE;
 }
 
 JSBool randFloat(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
 {
-	ValidateArgs("", cx, argc, argv, __FUNCTION__);
+	if(argc!=0 && argc!=2) {
+		JS_ReportError(cx, "randFloat: requires 0 or 2 arguments but got %d", argc);
+	}
+
+	jsdouble r;
+
+	if(argc==0) {
+		r = RandFloat();
+	}
+	else {
+		if(!JSVAL_IS_NUMBER(argv[0])) {
+			JS_ReportError(cx, "randFloat: argument 1 must be a number");
+		}
+		if(!JSVAL_IS_NUMBER(argv[1])) {
+			JS_ReportError(cx, "randFloat: argument 2 must be a number");
+		}
+
+		jsdouble minVal, maxVal;
+		JS_ValueToNumber(cx, argv[0], &minVal);
+		JS_ValueToNumber(cx, argv[1], &maxVal);
+		
+		if(maxVal < minVal) {
+			JS_ReportError(cx, "randFloat: argument 2 must be greater than or equal to argument 1");
+		}
+
+		r = RandFloat(minVal, maxVal);
+	}
 	
-	jsdouble r = RandFloat();
 	JS_NewDoubleValue(cx, r, rval);
 	return JS_TRUE;
 }
@@ -315,7 +350,7 @@ JSBool createObjectGroup(JSContext *cx, JSObject *obj, uintN argc, jsval *argv,
 	delete placer;
 	delete constr;
 
-	*rval = ret;
+	*rval = BOOLEAN_TO_JSVAL(ret);
 	return JS_TRUE;
 }
 
diff --git a/source/tools/rmgen/clumpplacer.cpp b/source/tools/rmgen/clumpplacer.cpp
index ea47c642fc..3ef58e51d7 100644
--- a/source/tools/rmgen/clumpplacer.cpp
+++ b/source/tools/rmgen/clumpplacer.cpp
@@ -19,6 +19,8 @@ ClumpPlacer::~ClumpPlacer()
 }
 
 bool ClumpPlacer::place(class Map* m, Constraint* constr, std::vector<Point>& retVec) {
+	// TODO: use a 2D array or hash set instead of a STL set for speed
+
 	if(!m->validT(x, y) || !constr->allows(m, x, y)) {
 		return false;
 	}
diff --git a/source/tools/rmgen/convert.cpp b/source/tools/rmgen/convert.cpp
index 0c2c948355..10e80792db 100644
--- a/source/tools/rmgen/convert.cpp
+++ b/source/tools/rmgen/convert.cpp
@@ -205,12 +205,15 @@ ObjectGroupPlacer* ParseObjectGroupPlacer(JSContext* cx, jsval val) {
 			elements.resize(array.size());
 			for(int i=0; i<array.size(); i++) {
 				string type;
-				int count;
-				float distance;
+				int minCount, maxCount;
+				float minDistance, maxDistance;
 				if(!GetStringField(cx, array[i], "type", type)) return 0;
-				if(!GetIntField(cx, array[i], "count", count)) return 0;
-				if(!GetFloatField(cx, array[i], "distance", distance)) return 0;
-				elements[i] = new SimpleGroup::Element(type, count, distance);
+				if(!GetIntField(cx, array[i], "minCount", minCount)) return 0;
+				if(!GetIntField(cx, array[i], "maxCount", maxCount)) return 0;
+				if(!GetFloatField(cx, array[i], "minDistance", minDistance)) return 0;
+				if(!GetFloatField(cx, array[i], "maxDistance", maxDistance)) return 0;
+				elements[i] = new SimpleGroup::Element(type, minCount, maxCount, 
+					minDistance, maxDistance);
 			}
 			return new SimpleGroup(elements, tileClass, avoidSelf, x, y);
 
diff --git a/source/tools/rmgen/random.cpp b/source/tools/rmgen/random.cpp
index 4bfb70e8be..3d5974b106 100644
--- a/source/tools/rmgen/random.cpp
+++ b/source/tools/rmgen/random.cpp
@@ -17,4 +17,12 @@ float RandFloat() {
 	return float(rng()) * (1.0f/4294967296.0f);
 }
 
+float RandFloat(float minVal, float maxVal) {
+	return minVal + RandFloat() * (maxVal - minVal);
+}
+
+int RandInt(int minVal, int maxVal) {
+	return minVal + RandInt(maxVal - minVal + 1);
+}
+
 
diff --git a/source/tools/rmgen/random.h b/source/tools/rmgen/random.h
index ef1a9e51f0..02384b7914 100644
--- a/source/tools/rmgen/random.h
+++ b/source/tools/rmgen/random.h
@@ -1,3 +1,5 @@
 void SeedRand(unsigned long seed);
-int RandInt(int maxVal);
-float RandFloat();	  // in range [0,1)
+int RandInt(int maxVal);	// in range [0, maxVal-1]
+float RandFloat();			// in range [0, 1)
+int RandInt(int minVal, int maxVal);		// in range [minVal, maxVal]
+float RandFloat(float minVal, float maxVal);	// in range [minVal, maxVal)
diff --git a/source/tools/rmgen/simplegroup.cpp b/source/tools/rmgen/simplegroup.cpp
index 236771056f..24705899c6 100644
--- a/source/tools/rmgen/simplegroup.cpp
+++ b/source/tools/rmgen/simplegroup.cpp
@@ -3,15 +3,22 @@
 #include "point.h"
 #include "random.h"
 #include "map.h"
+#include "rmgen.h"
 
 using namespace std;
 
 SimpleGroup::Element::Element(){
 }
 
-SimpleGroup::Element::Element(const std::string& t, int c, float d):
-	type(t), count(c), distance(d)
+SimpleGroup::Element::Element(const std::string& t, int minC, int maxC, float minD, float maxD):
+	type(t), minCount(minC), maxCount(maxC), minDistance(minD), maxDistance(maxD)
 {
+	if(minCount > maxCount) {
+		JS_ReportError(cx, "SimpleObject: minCount must be less than or equal to maxCount");
+	}
+	if(minDistance > maxDistance) {
+		JS_ReportError(cx, "SimpleObject: minDistance must be less than or equal to maxDistance");
+	}
 }
 
 SimpleGroup::Element::~Element() {
@@ -20,11 +27,14 @@ SimpleGroup::Element::~Element() {
 bool SimpleGroup::Element::place(int cx, int cy, Map* m, int player, bool avoidSelf,
 								 Constraint* constr, vector<Object*>& ret) {
 	int failCount = 0;
+	int count = RandInt(minCount, maxCount);
 	for(int i=0; i<count; i++) {
 		while(true) {
-			float ang = RandFloat()*2*PI;
-			float x = cx + 0.5f + distance*cos(ang);
-			float y = cy + 0.5f + distance*sin(ang);
+			float distance = RandFloat(minDistance, maxDistance);
+			float angle = RandFloat(0, 2*PI);
+
+			float x = cx + 0.5f + distance*cos(angle);
+			float y = cy + 0.5f + distance*sin(angle);
 
 			if(x<0 || y<0 || x>m->size || y>m->size) {
 				goto bad;
diff --git a/source/tools/rmgen/simplegroup.h b/source/tools/rmgen/simplegroup.h
index 7e7feeb9e4..b3686f9ac3 100644
--- a/source/tools/rmgen/simplegroup.h
+++ b/source/tools/rmgen/simplegroup.h
@@ -10,11 +10,12 @@ public:
 	class Element {
 	public:
 		std::string type;
-		int count;
-		float distance;
+		int minCount, maxCount;
+		float minDistance, maxDistance;
 		
 		Element::Element();
-		Element::Element(const std::string& type, int count, float distance);
+		Element::Element(const std::string& type, int minCount, int maxCount,
+			float minDistance, float maxDistance);
 		Element::~Element();
 
 		bool place(int cx, int cy, class Map* m, int player, bool avoidSelf,
diff --git a/source/tools/rmgen/smoothelevationpainter.cpp b/source/tools/rmgen/smoothelevationpainter.cpp
index 2d2dabebb3..e80ed0a080 100644
--- a/source/tools/rmgen/smoothelevationpainter.cpp
+++ b/source/tools/rmgen/smoothelevationpainter.cpp
@@ -28,6 +28,8 @@ bool SmoothElevationPainter::checkInArea(Map* m, Area* a, int x, int y) {
 }
 
 void SmoothElevationPainter::paint(Map* m, Area* a) {
+	// TODO: Use a 2D array instead of STL maps and sets for speed
+
 	map<Point, int> saw;
 	map<Point, int> dist;