cURL and shell scripts

Help!
I have just recently started learning some Applescript and am moving on now to Xcode.

I have already written an AppleScript which fetches the latest build number of a piece of software from a URL, held in a text file, and uses that to download the latest nightly build of this app. I am now trying to put a UI around it with progress bar. I’ve adapted it for AppleScript Obj-C but can’t seem to get it to work. Can anyone help? Or point me in the right direction?
It doesn’t even seem to get beyond the first curl according to the console logs, it gives the error "couldn’t resolve host ‘value’

on updateChromium_(sender)
		
		--obtain latest build number
		latest's setStringValue_(do shell script" curl http://example/com/latest" as string)
		build_label's setStringValue_(latest)
		progress_bar's incrementBy_(10)
		
		
		--set local directory info
		remFile's setStringValue_("file.zip" as string)
		locDir's setStringValue_("$HOME" as string)
		locFile's setStringValue_("file.zip" as string)
		
		--download latest build using build number in the_source
		do shell script "curl [url=http://example.com/]http://example.com/"[/url] & latest & "/" & remFile & " -o " & locDir & locFile
		build_label's setStringValue_(latest as string)
		progress_bar's incrementBy_(10)
		
		--unpack and copy
		do shell script "unzip -o " & locDir & locFile & " -d " & locDir
		progress_bar's incrementBy_(15)
		
		--move existing application and copy new
		try
			do shell script "cp -pR /Applications/Example.app /Applications/Example.old.app"
			do shell script "rm -R /Applications/Example.app"
		end try
		
		do shell script "mkdir -p /Applications/Example.app"
		do shell script "mkdir -p /Applications/Example.app/Contents"
		do shell script "cp -pR " & locDir & "file/Example.app/Contents /Applications/Example.app"
		progress_bar's incrementBy_(15)
		
		--Cleanup folders and files
		do shell script "rm -R " & locDir & "file*"
		progress_bar's incrementBy_(15)
		try
			do shell script "rm -R /Applications/Example.old.app"
		end try

	end updateChromium_

Model: Xcode 3.2.1 64-bit, Macbook Pro
Browser: Safari 531.21.10
Operating System: Mac OS X (10.6)

Should “example/com” be “example.com”?

Sorry, thats just a typo when i was replacing the actual URL’s I’m using.

Put in some log calls and find out exactly where it’s getting to.