This is doable, but it will require some custom code at the moment because smart home monitor doesn’t currently check if your lock status is locked or unlocked. Clearly it should, so it seems likely that it should have this capability in the future, but there’s no specific time line for it so I don’t know if you want to wait to see if it shows up in the standard choices.
If you want to go ahead with custom code, that’s less complicated than it sounds because other people are already doing it. So it’s mostly a matter of copy and paste what they did into your own account.
The following FAQ explains how you use someone else’s custom code.
If that sounds like something you’d like to go ahead with, let us know, and community members can help point you towards the pieces that you need. I’m pretty sure that everything you need already exists in the community, but you will have to publish the various pieces to yourself before you can configure your set up.
Like many things in the SmartThings, this is neither into intuitive nor straightforward. But it is possible.
Before we go any further down this route, are you using a US model hub? Or a UK model?
The reason I ask is that there are third party apps that do provide rules engines which are much more similar to the one which Vera has, and which fill in the gap for a lot of people who don’t want to fool with code. But right now these are not working for the UK model hub.