Does not show

That is standard behaviour if the module isn't enabled. Can you check that it is? If so, can you check that you have the "Check System Variables" permission?

The same thing is happening for me. The status report shows 3 variables and a link to the report, which redirects to the main report page, even when I navigate to admin/reports/variablecheck.

The module IS enabled.

Sorry, but I cannot for the life of me reproduce this problem when running as user #1. It is what happens when your user does not have the 'Check System Variables' permission, like I said.

I've changed the UI a bit, so that if the user does not have this permission, the system status page doesn't show a link, but a message about permissions instead. Can you check the new 7.x-1.x-dev version that will shortly be released?

In the absence of further comments, I'm closing this issue, assuming the problem is resolved.

Sorry to comment on a closed issue. This happened to me in Drupal 6 and it had to do with duplicate menu items in the menu_links table. It turns out that Admin menu was creating some duplicate links though I am guessing by design. If you follow this thread, there are some possible solutions.

I have not heard of this issue popping up in Drupal 7 though so it's just a shot in the dark. At any rate, once I deleted the duplicate /admin/reports entry in MySQL (Drupal 6), I was then able to get to /admin/reports/variablecheck on my site and see the offending code.

Obviously the path in Drupal 7 is different and you will want to backup your db and test this on a local dev. BTW, awesome module, this!