Several years ago we did some work with ARIS. It was not so much that ARIS was a good option for importing data for the CMDB, it was just that it was the incumbent product. It is still a popular choice out there and is good at what it does.
More recently we did some initial work looking at TROUX. This was leaning more towards Application Portfolio management, but it could be used for BPM as well. We didn't take it too far (project budget ran out) but it looked good also.
The big challenge for these tools is the same as exists for the CMDB itself. Does the cost of maintenance effort begin to limit the accuracy and currency of the data. If the BPM tool is baked into the SDLC/methodology then you have a trusted source. If not, don't put that data into the CMDB.
I believe both ARIS and TROUX have some form of Atrium CMDB integration, but neither were very serious about it, and they may have been FROM CMDB rather than TO CMDB. I would suggest that you would want to look at federation-type concepts to access/see the BPM data in other tools.
We used Flat File feed to Load Same data Into CMDB. Spoon jobs used to Create CI and Relationship CI.