A few seconds search of this forum gives a few ways to identify versions, like bundle.list on the karaf console.
But that’s fine, assume as-it-comes version 2.4.0
There is a problem with roller STOP in 2.4.0 as I understand it, and you want to use that. 2.5 versions will have a STOP fix. There’s a “but”…
That’s by design, right or wrong.
Lots about it here
Me, I’d stick with 2.4 and set up a roller Item linked to nothing, and have a rule that listened for commands and issued MQTT acions directly. The rule can also make a guess about the expected position and update the roller Item state.
Maybe review when 2.5M2 is available.