Gulf War, Incurred does not directly equal combat related. There is a short list of disabilities from the VA that create a presumptive condition for the service components to assume they are incurred by instrumentality of war rather than proof of direct combat (or simulated combat) causes. This list includes certain types of cancers, breathing conditions, and in some situations GI conditions. Anything other than those specifically listed disabilities must be individually proved by the applicant for combat related approval.
Hypothetical example: If you are under direct fire maneuvering in Afghanistan and fall in a hole, breaking your leg, you are likely to be approved for CRSC. If you are running for PT in Afghanistan, without hostile action, and you fall in a hole and break your leg, you are likely to be denied for CRSC. Your physical disposition on the planet is not the cause of your disability, your actions taken under direct fire were.
Personal Examples: I was recently approved for instrumentality of war (Afghanistan) under presumptive condition for Asthma (referred condition of my MEB), and approved for tinnitus, but denied for IBS (not sure why but they said it's not presumptive for my deployments) and denied for several other injuries including shoulder injury and foot injuries that were incurred during Ranger School. Ranger didn't make medical records of exact cause of injury so I can't prove it, regardless of the fact that it was incurred during simulated war. There was no presumption of cause of injury even though my injury documentation stated treatment from 5th RTB. HRC shrugged and said provide better records to prove it happen during said simulated war.
As for iPerms? Can't say I have as I am not eligible for CRSC, but keep us posted if you see something there, tbh, this was the first I was aware you could get into iPERMS after getting out, and I just downloaded my records 
