FSX for some reason doesnt have ILS for all major airport runways and im wondering if there is any way to manually fix this in some cfg file. What are AFCAD files, and do they have anything to do with this? Is there any way to input missing ILS approaches glideslope/localizer into major airports that have them missing on key runways?
Yes you can fix or update ILS runways for all airports, stock or after market payware.
I would recommend the freeware ADEX which works for both FSX and FS9.
Here's the link to the site:
http://www.airportdesigneditor.co.uk/It's very easy to fix or add ILS and there is plenty of instructions and documentation on that site. You can also do a lot of other stuff with ADEX like add parking spots, assign airline parking codes, place or remove buildings, etc. The possibilities of what you can do are almost endless.
BTW, after you work on an airport dont forget to import the stock approaches so that they show up in your default GPS if you use it.