Installing fiberglass over an existing court that is cracked is the worst thing you can do to your court, unfortunately the only cure the repair a court that is largely cracked is to rectify the stone base, drainage & replace the existing asphalt. When fiberglass is installed over cracks, the moisture will rise through the crack and will cause the fiberglass to separate from the substrate.

Commonly we advise tennis court owners to leave the cracks alone, unless the area has shifted and can be a hazard. Esthetically if you fill the cracks without surfacing the entire court it will look worse, thus if you fill the cracks and only patch the cracked area, it is impossible to match the existing colour and your court will look wrost.