Related fixes are grouped together here. This includes original Yellow bugs and problems corrected while adding Yellow++ features.

• Removed the original 1-in-256 miss when a move should have maximum accuracy.
• Fixed guaranteed-critical handling and Focus Energy lowering critical-hit chances instead of raising them.
• Prevented Reflect and Light Screen from overflowing, and a battle freeze against extremely low defensive stats.
• Corrected effectiveness messages against dual-type Pokémon.
• Corrected hit restrictions for HP-draining moves and Dream Eater.
• Added protection against Substitute leaving its user at zero HP, though it can still fail in some cases where enough HP remains.
• Fixed healing moves failing when the Pokémon is missing exactly 255 or 511 HP.
• Fixed interrupted Dig/Fly leaving Pokémon permanently invulnerable.
• Fixed Psywave causing link-battle desynchronization and Bide damage carrying over after battle.
• Trainer HP displays update after an opponent uses a healing item.
• Status-curing items no longer reset unrelated stat changes.
• Corrected the female Cooltrainer's low-HP switching behavior.
• Captured transformed Pokémon are no longer automatically treated as Ditto.
• Unseen ghosts cannot be identified without the Silph Scope or reveal their hidden species in the Pokédex.
• PP restoration correctly accounts for PP Ups.
• Fixed skipped moves when gaining multiple levels, incorrect evolution moves and level-one entries, and wrong moves or stats after evolution.
• Fixed TM-use crashes and Substitute-related problems.
• Fixed sleep duration, healing while asleep, and waking behavior.
• Ineffective item uses no longer raise Pikachu's friendship.
• Fixed Pokémon seen/caught tracking and Koffing's missing Pokédex entry.
• Corrected wild shiny generation and scripted shiny gifts.
• Fixed Nuzlocke encounter tracking in two areas and Rare Candy reviving fainted Nuzlocke Pokémon.
• Corrected seeded-randomizer results and setup prompts.
• Corrected trainer team selections, custom movesets, and Giovanni/Lance shiny assignments.

• Fixed the north–south Underground Path's dimensions and a faulty encounter boundary.
• You can move immediately after returning Mr. Fuji home.
• Resetting no longer bypasses Safari Zone restrictions.
• Corrected collisions, including Pikachu following through expanded maps and a misplaced following-Pikachu position.
• Corrected NPC movement, delays, and visibility at map edges.
• Prevented landing on NPCs after jumping ledges.
• Holding A at the Route 12 binoculars no longer stops NPC movement.
• Fixed the Route 16 sign, Route 2 gate tiles, and a Viridian Cut tree.
• Itemfinder detects hidden items at map edges.
• Fixed Escape Rope animation and music after falling through a hole while cycling.
• A Poké Doll can no longer bypass the ghost Marowak story event.
• Overworld sprites reload correctly after using the Poké Flute.

• The hidden 40-coin stash gives all 40 coins, previously only 20.
• Corrected slot-machine odds and selection of a nonexistent lucky machine.
• Fixed slot-machine graphics loading.

• Corrected battle transitions in dungeon maps.
• Fixed the opponent's Double Edge animation, missing backsprite corners, and tearing during sprite slides.
• Fixed Strength-boulder dust and the Pokémon Center healing-machine flash.
• Removed two unwanted splash-screen stars.
• Psychic, Psywave, and Night Shade now shake the full intended screen area.
• Fixed distorted Articuno binocular cries and unwanted fossil cries in the museum.
• Corrected audio pitch problems, interrupted item jingles, missing Oak's Lab music channels, and victory music playing at the wrong time.
• Corrected player movement and shrinking animations, Hall of Fame portraits, party minisprites, and status-screen graphics.
• Fixed shiny, evolution, and intro colors, including the player changing gender after viewing a shiny Pokémon.
• Talking to Pikachu no longer changes overworld sprite colors.
• Fixed back-sprite colors, monochrome icon colors, and the Water type icon's shading.
• Corrected intro slowdown, cries, and palettes.

• Fixed leftover move-menu text, party graphics overwriting battle sprites, and status icons missing in PC summaries.
• Fixed Pokédex evolution text overlapping its frame and other status/Pokédex layout issues.
• Corrected font characters, naming text, missing punctuation, item descriptions, and grammar.
• EXP messages correctly display five-digit rewards.
• Fixed held buttons triggering unwanted actions, repeated Bag SELECT actions, menu exits, and brief overworld flashes.
• Bicycle selection opens its action menu; both Bag use and SELECT shortcuts respect forced cycling.
• Corrected storage submenus, selection, movement, and cancellation behavior.
• Fixed older saves freezing on Continue after ROM updates.

Further loading and responsiveness improvements are included on Everyday features.