Yes, especially with sun exposure. Storing discs out of direct sunlight helps preserve color.
If properly set and rinsed, it shouldn't. Incomplete setting may cause smearing or bleeding.
Premium plastics like Champion, Star, ESP, and Opto are best. Base plastics like DX or Pro D typically don't take dye well. If you have a specific plastic you are curious about, use the Dyers Guild's Disc Dyeing Acceptability Chart to search lookup your plastic.
Yes, as long as the disc is PDGA-approved and not altered in a way that changes its flight or violates rules (e.g., added weight or texture).
