I have created a field called PROCESS via Fields » Field transformations
I could not see in the field appear in the search results.
Also, I could not set up a field using Field extractions as it only works on data _raw field.
Try this for your regular expression:
\/flcc-logs\/(?<PROCESS>[^\/]+)
You can also do this "live" as part of your search:
(your search)
| rex "\/flcc-logs\/(?<PROCESS>[^\/]+)"