I must have missed this thread.
The way I have always added thumbnails to objects is similar to X:
- start a new world, hide the ground or delete it
- go to atmosphere color
- go to change it, but click on other...
- go to the RGB tab
- change all values to 128
- now you have a grey sky
- position your model well for a screenshot
- take a pic of it and open it in a good graphics editing program
- change the height to 128 (the wifth of all thumbnails in the gallery is 128, but it doesnt matter)
- save it as thumbnail.png (as a png file)
- open the a2c file in a zip program
- paste in the png picture you just edited
- done
and thats not all you can hack in Alice:
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I have mostly moved on from Alice, but may still respond to messages if important [¬º-°]¬