Thanks for the help, appreciate it!

I added +www.example.com/* to scan rules but no luck...

This is what the log says (I edited the links for privacy):

---
HTTrack3.47-25+htsswf+htsjava launched on Mon, 11 Nov 2013 14:17:31 at
<http://example.com/landing-pages/landing-page.shtml> +*.png +*.gif +*.jpg
+*.css +*.js -ad.doubleclick.net/* -mime:application/foobar +www.example.com/*


(winhttrack -qwC2%Ps2u1%s%uN0%I0p3DaK0H0%kf2A25000%f#f -F "Mozilla/4.5
(compatible; HTTrack 3.0x; Windows 98)" -%F "<!-- Mirrored from %s%s by
HTTrack Website Copier/3.x [XR&CO'2013], %s -->" -%l "en, *"
<http://example.com/landing-pages/landing-page.shtml-O1> "D:\My
Folder\landing-page" +*.png +*.gif +*.jpg +*.css +*.js -ad.doubleclick.net/*
-mime:application/foobar +www.example.com/* ) 

Information, Warnings and Errors reported for this mirror: 
note:	
the hts-log.txt file, and hts-cache folder, may contain sensitive information,
such as username/password authentication for websites mirrored in this project


do not share these files/folders if you want these information to remain
private 

14:17:33	Error: 	"Not Found" (404) at link www.googletagmanager.com/gtm.js?id=
(from <http://example.com/landing-pages/landing-page.shtml>)

HTTrack Website Copier/3.47-25 mirror complete in 2 seconds : 3 links scanned,
1 files written (16117 bytes overall) [7821 bytes received at 3910 bytes/sec],
16117 bytes transferred using HTTP compression in 1 files, ratio 37%, 1.5
requests per connection 
(1 errors, 0 warnings, 0 messages)
---

So still no images downloaded...