diff --git a/lib/chrome.js b/lib/chrome.js
index 09fafa1..db3f5a8 100644
--- a/lib/chrome.js
+++ b/lib/chrome.js
@@ -36,7 +36,7 @@ var ChromeObject = function() {
 
 	this.setProfile = function(profileName, installedDir) {
 		this.profileName = (profileName == "Default" ? "Chrome" : profileName);
-		this.installedDir = installedDir;
+		this.setInstalledDir(installedDir);
 		this.workingDirectory = this.workingDirectory.replace(":installedDir", this.installedDir);
 		this.binPath = this.binPath.replace(":installedDir", this.installedDir);
 		//this.binPath = this.binPath.replace(":installedDir", "Chrome");
@@ -44,12 +44,18 @@ var ChromeObject = function() {
 	};
 
 	this.setUserDataDir = function(dirname) {
-		this.userDataDir = dirname;
+		if (dirname != null) {
+			this.userDataDir = dirname;
+		} else {
+			this.userDataDir = SHELL.getPathOfMyDocuments() + "\\UserData_Chrome_" + this.profileName;
+		}
 		return this;
 	};
 
 	this.setInstalledDir = function(dirname) {
-		this.installedDir = dirname;
+		if (dirname != null) {
+			this.installedDir = dirname;
+		}
 		return this;
 	};
 	
@@ -75,6 +81,7 @@ var ChromeObject = function() {
 	
 	this.setDebuggingPort = function(n) {
 		this.debuggingPort = (typeof(n) !== "number" ? this.debuggingPort : n);
+		return this;
 	}
 	
 	this.setPageId = function(s) {
@@ -181,7 +188,11 @@ var ChromeObject = function() {
 			}
 
 			cmd.push("--profile-directory=\"" + this.profileName + "\"");
-			cmd.push("--proxy-server=\"" + this.proxy.protocol + "://" + this.proxy.host + ":" + this.proxyPort + "\"");
+			
+			if (this.proxy != null) {
+				cmd.push("--proxy-server=\"" + this.proxy.protocol + "://" + this.proxy.host + ":" + this.proxyPort + "\"");
+			}
+			
 			cmd.push("--user-data-dir=\"" + this.userDataDir + "\"");
 			cmd.push("\"" + url + "\"");
 			shell.runAs(this.binPath, cmd);
@@ -198,7 +209,7 @@ var ChromeObject = function() {
 	
 	this.getPageList = function() {
 		if (this.debuggingPort > 0) {
-			return HTTP.get("http://127.0.0.1:" + this.debuggingPort + "/json");
+			return JSON.parse(HTTP.get("http://127.0.0.1:" + this.debuggingPort + "/json"));
 		} else {
 			console.error("Remote debugging unavailable");
 			return [];
@@ -225,19 +236,33 @@ var ChromeObject = function() {
 	};
 	
 	this.sendPageRPC = function(method, params) {
-		if (this.pageId != "") {
-			this.ws.send("ws://127.0.0.1:" + this.debuggingPort + "/devtools/page/" + this.pageId, JSON.stringify({
-				"id": pageEventId,
-				"method": method,
-				"params": params
-			}));
-			pageEventId++;
-			console.info("ChromeObject().sendPageRPC() -> Sent");
-		} else {
-			console.error("pageId not specified");
+		var result = null;
+
+		try {
+			if (this.pageId != "") {
+				result = this.ws.send("ws://127.0.0.1:" + this.debuggingPort + "/devtools/page/" + this.pageId, JSON.stringify({
+					"id": pageEventId,
+					"method": method,
+					"params": params
+				}));
+				pageEventId++;
+				console.info("ChromeObject().sendPageRPC() -> Sent");
+			} else {
+				var pageList = this.getPageList();
+				if (pageList instanceof Array && pageList.length > 0) {
+					this.pageId = pageList[0].id;
+					if (this.pageId != "") {
+						result = this.sendPageRPC(method, params);
+					} else {
+						console.error("Got invaild list of pages");
+					}
+				}
+			}
+		} catch (e) {
+			console.log("ChromeObject.sendPageRPC() -> " + e.message);
 		}
 
-		return this;
+		return result;
 	};
 
 	this.navigate = function(url) {
@@ -247,14 +272,39 @@ var ChromeObject = function() {
 	};
 
 	this.evaluate = function(expression) {
-		return this.sendPageRPC("Runtime.evaluate", {
-			"expression": expression
-		});
+		try {
+			return this.sendPageRPC("Runtime.evaluate", {
+				"expression": expression
+			});
+		} catch (e) {
+			console.error("ChromeObject.evaluate() -> " + e.message);
+		}
+	};
+
+	this.close = function() {
+		return this.sendPageRPC("Browser.close", {});
 	};
 
 	this.focus = function() {
-		return this.evaluate("window.focus()");
+		if (this.debuggingPort > 0) {
+			try {
+				var oAutoIt = CreateObject("AutoItX3.Control");
+				var pageList = this.getPageList();
+				for (var i = 0; i < pageList.length; i++) {
+					if (pageList[i].id == this.pageId) {
+						oAutoIt.WinActivate(pageList[i].title);
+					}
+				}
+			} catch (e) {
+				console.error("ChromeObject.focus() -> " + e.message);
+			}
+		}
 	};
+	
+	this.blur = function() {
+		return this.evaluate("window.blur()");
+	};
+	
 };
 
 exports.create = function() {
@@ -266,17 +316,15 @@ exports.start = function(url, proxyPort, profileName, userDataDir, installedDir)
 		.setProxyPort(proxyPort)
 		.setProfile(profileName, installedDir)
 		.setUserDataDir(userDataDir)
-		.setInstalledDir(installedDir)
 		.open(url)
 	;
 };
 
-exports.startWithDebugging = function(url, proxy, profileName, userDataDir, installedDir, debuggingPort) {
+exports.startWithDebugging = function(url, proxy, profileName, debuggingPort) {
 	return (new ChromeObject())
 		.setProxy(proxy)
-		.setProfile(profileName, installedDir)
-		.setUserDataDir(userDataDir)
-		.setInstalledDir(installedDir)
+		.setProfile(profileName, null)
+		.setUserDataDir(null)
 		.setDebuggingPort(debuggingPort)
 		.open(url)
 	;