BACK DOOR CHEAT, "Round About" has a built in cheat mode that'll start you with 7 "ships" (lives) instead of 3, if you press and hold all 3 console buttons (Option, Select, Start) on the title screen and then use fire button to begin. This absolutely does not work on my emulator. My Apple OSX 10.4 USB keyboard can't begin to see 3 significant keys held down at once. Call this another emulator bug??
The download we got here is a few K oversized crack dump. "Round About" works as a single segment in addresses $0800 thru $7FD5 and begins running at $8C1. The Reset button can't be trapped, Round About employs the Select button to behave like Reset. The code beginning at address $800 reads $"70 70 F0 ..." (display list data, hence the $8C1 start address).
CHEAT MODE unlimited lives, file versions - edit 4 bytes in the file to change the sequence $"C6 17 30 06" to become $EAEAEAEA. The file here now 33008 bytes has this at offsets $51D thru $520, whereas my 30690 bytes file has it at offsets $3B1 thru $3B4.
Game has 24 levels very hard to see them all without cheating. The words describing enemies and words used to congratulate you are, how can I say, the authors knew the meaning of "fly" before that sense became popular in the 1990s.
Folks downloading from "pigwa.net" Be Warned, I've identified so high percentage of corrupted programs from that site it's hard to believe they're not doing it on purpose. Their Round About found on (Homesoft) disk number "Spiele 86" has a corruption, the sequence $"BD B1 28" should instead be $"BD 4C 16" though I couldn't see what this did to the game.