I first thought you were referring to false update notifications, so I checked the first two apps.
Reported latest version: 4.0.6.
Actual latest version (as downloaded from Mac Informer): 4.0.6.
Actual latest version (as downloaded from reggieashworth.com): 4.0.6.
Reported version: 2.1.3.
Actual version: 2.1.3.
No discrepancies there. I'm not saying that the app is infallible, but the idea is that it will notify you when there's a known update (those will crop up in the Updates tab). There's no need to download apps manually to check whether there are.
As for older downloads - I'll look into those. There does sometimes happen to be a bit of a delay between the moment when an update gets released and the moment when we get to know about it. But these don't actually cause users to install older versions of apps, as they don't bring up any update notifications.