They'd be mining on Rura Penthe, not crafting. You can't have a production economy without mining.
Mmmh, Klingon does not live on raw meat alone. With all the cooking and baking we'll have to have a fire, and fire requires . . . wood. So wood cutting won't be far behind.
And now that STO toons will be able to properly sit in chairs we must have . . . furniture crafting! Another use for wood too.
Well, the way I described it was probably too short, so I'll give it another shot.
Rura Penthe is not just an asteroid, but a planetoid with normal gravity and atmosphere.
So there would be enough space for more than one Gulag.
And since the concept of Rura Penthe in ST6 was that of an analogy to Siberia I'd like to point out that
the Soviets had more than one kind of Gulag, they also had Gulags filled with scientists who conducted research, though they never received the credid for their work.
And what better place to put such a research Gulag than Rura Penthe?
People would still have the same problems leaving AND since it is already common knowledge that there is such an installation one or two additional transports every now and then bringing prisoners that are not meant for the primary Gulag would hardly be noticed.
Woodcrafting...for the Feds but probably not for the Klingons, they seem to dislike anything "soft" , and they sleep on metal shelfs.
Since wood is most likely still too soft for them how about some metal crafting for them instead?