What is the use of the parameter SP_OCF_FK_ANALYSIS?
The parameter is used to as follows. The parameter, if set to its default value of 1, will force SharePlex activation process to do the Foreign Key analysis for tables being brought in to replication. If one of the parent or child table is excluded from replication, then the analysis will generate a message in the event log, but will move on to the next table. Such messages will help by alerting the users about the absence of related table(s) in the config file. If the parameter is enabled, it will require more work on the part of activation process to do such analysis which will require additional time if numerous tables with parent/child relationship are involved. But the positive side of this is, it will log useful info in event log about missing objects involved in such relationship.
If both parent and child tables are not included in replication but only one of them is, and if this applies to most related tables in replication, then leaving the parameter at its default value of 1 may not be efficient and it is better to disable it. This is applicable if the related tables were omitted from replication intentionally and logging of this fact is of no significance to the user.