nw-logparsers where you can see the raw log parsers, diff between versions, and event make your own pull and changes and commit them back to be reviewed by the live team. Or you can contribute any custom parsers that you have developed and feel comfortable sharing to help others in the RSA NetWitness community.
The other project are some Yara rules that you could try in the Malware appliance I guess
Can't help you with the QA part, other than opening a case when you see issues like this... we hope to have only positive changes when parsers change but ...
You can probably get GitHub to notify you of changes to the project or to specific parsers but by GitFoo is a bit weak at the moment.
When is RSA going to start using their populated fields to start documenting changes from previous versions they support ?
For instance, look at this screenshot, there are various fields that could be used for populating needed information for users to make educated / informed decisions on whether they should pull this into their environment or not. RSA needs to start populating fields for diffs on what was made/how they improved the parser. The comments section would be agood start for RSA to populate updated changes made by RSA. Those scripts mentioned above are nice, but most small/medium companies wont have the time to pull down parsers, analyze this information, and identify if they need them or not in their environment.