Why does the grain lines from your graining pen go chubby when you topcoat it?

Don't spray so much aerosol over the grain. The aerosol is causing the graining pen to float. Spray a couple of light mist coats over the area first to lock it down first.

Scratch Remover Marker ink tends to crawl when applied to some surfaces.

Hi Tech finishes don't allow solvents from pen material to bite in. These surfaces need to be scuffed first. Or: Surface may have a wax or polish contamination. Clean the surface with De Waxer 741.

Scratch Remover Marker colour in marker is off shade.

Marker was not thoroughly agitated before using. Shake pen and re-flow material to flush nib. Or: User is not allowing for batch-to-batch lot shade differences. (Commercially allowable difference from lot to lot is expected in the coatings industry.)

Scratch Remover marker ink will not pass through nib.

Cap was left off for prolonged period causing resin to harden in nib. Soak nib in lacquer Thinner or white spirit. Or: Ink has been used up. Replace marker.