Business Process Management or Workflow integration?

Hello,

We sell installed products (like water heaters, furnaces, etc.) through OpenCart. We’d like to integrate a business process management tool in OC, if possible - something to track an order from inspection, to ordering of parts, to post-sales support, etc. I’ve looked at a few open-source BPM tools, but would like to know if anyone has any experience with this.I went through many resources Business Process Management Video for help but wasnt satisfied.

Any other suggestions?
Any help will be appreciated.
Thank you.