We are still on 6.0.x and cannot upgrade immediately, but would like to try out this new app.
It appears to require 6.2 from what is listed on Splunkbase, however in our experience most apps seem to work fine within a given major version of Splunk such as 6.1 to 6.2 so you might be fine on 6.0.x.
However, I'd probably not recommend trying to get an app supported on any 6.x installation running in a 5.0 environment as quite a bit changed within the core product. If you have a staging, QA, or Dev environment I'd say try their first and then post your results here to share with others.
Is this actually the app that won the SCCM app contest? https://splunkbase.splunk.com/app/2750/
Correct, this was the app that won. You could always reach out directly to the dev of the app as well to see if any testing was performed prior to 6.2