cross linking context works only on some pages?

this is an odd one.
I have my mobile site as another context subdomain.

I have set in both the web and mobile context the base_url and site_url.
When I link to images from the mobile site I use but it only works on some pages and on others it looks as broken image link?

both pages have same template and I can't figure how can it be.

here is a working page:
http://m.zebrasecurity.com/aldelo_point_of_sale

and here is a non working page:
http://m.zebrasecurity.com/facility_wifi_network
anyone have any idea what it can be?

What is [[+web]] representing? path to main context (main folder) or mobile context (m sub folder)?

If the path works in one page, I suppose it should work in another, of the same context, unless the actual files are missing.
The second link has at least 10 items reporting 404 error - a great deal of Javascript missing.

The one image, unifi-small.png, does not even exist in the image folder. Whereas the first link has pos.png, which exists.
Just a question of physical files.
If you want the http://m.zebrasecurity.com/ site to have its own images, best to populate its assets folder with all necessary files.
If you want the http://m.zebrasecurity.com/ site to use files stored on http://zebrasecurity.com/, best to make [[+web]] absolute, that is,
[[+web]]assets/image/image.png will, in whatever context, always produce
http://zebrasecurity.com/assets/image.png instead of
http://m.zebrasecurity.com/assets/image.png

Are you sure you don't want this?

Yea right? I reckoned he was aware of what he was doing...and thus created a custom placeholder [[+web]]...
If not, then [[++site_url]] is the issue...

Still though, he'll need to make sure the [[++site_url]] points to a domain that has existing physical files

Thanks guys.
Yes I indeed wanted [[+web]] to redirect to the main site assets directory and to use the same images so I can upload from modx file manager.
I didn't realized I had created in the past actual directory on the server to hold the mobile images.
using [[++web]] now works as I wanted. thanks for the help.