I've just released Mixel Maker, a toolkit for making your own 3D point-and-click adventures with no code and nothing to install.

• Build places from a big library of ready-made pieces: buildings, furniture, lights, nature, animals, weather and sound
• Dress your characters in the Character Studio, with outfits from medieval to sci-fi
• Write the story in plain words ("Marta says…", "If the player has the key…"): conversations, inventory, puzzles, hints and endings, no scripting
• Play-test as you go, then export to a web page (perfect for itch.io) or Windows and Linux programs
• A five-minute guided tour, and a complete example mystery to take apart
Try the free demo in your browser (it does everything except export): https://retropixellabs.itch.io/mixel-maker
See what it makes: "Lights Out at Gull's Rest" is a free mystery made entirely with it: https://retropixellabs.itch.io/lights-out-at-gulls-rest
Your games are yours to give away or sell, royalty-free. Feedback very welcome!