As others have mentioned, you can simply ignore shallow gouges, compressions or scratches as they likely will have little to no effect on the ski, especially if they run lengthwise along the ski as opposed to across the base.
Toko does make a base repair powder in both black and clear that does a good job repairing minor scratches, gauges and such. It's readily available at many tuning supply shops. It includes full instructions. Basically,
1) Sprinkle the repair powder into the gauge or scratch that has been cleaned of any wax residue.
2) Cover with a clear plastic sheet (several sheets come with the repair powder kit).
3) Iron over the plastic sheet until the powder underneath melts.
4) Remove the plastic and use either a sharp steel scraper or sandpaper to remove any excess repair material.
If the compression, gauge or scratch is wide enough to allow you do so, first rough it up a little with sandpaper or even a pin before applying the powder for stronger repair.