I participated as an Artist for the GMTK'24 that went from August 16 to August 20, there was a team finder and they extended the delivery period by 1 hour (we had to convert all assets from SVG to PNG), what luck.
My experience was good. It made me realize my limitations and there were a few funny hiccups but we passed through those.
If there’s anything that I learned was that you shouls have all images in separate instead of an a single file with everything. This way the team has the freedom to re-arrange things whenever they want.