Mark Mandell - Gone Round In New Jersey
Lester,

No, the CA ["Super Glue"] will tend to soak in and then mess up your finishing routine. Shellac, however, will sand off easily. You can also use paste wax, like Johnson's, but you have to be careful not to get any inside the cracks as the epoxy won't stick to it.

For large cracks like my walnut piece, you should consider at least one butterfly inlay to stabilize the gap as seasonal wood movement will tend to open or close the gap and loosen the cured epoxy fill.

PS: You don't need to "prime" the inside surfaces of the cracks; the epoxy will get a better grip on the fibers if you don't.