Tip: When determining a time limit, remember that players won't be as familiar with the level as you are. If you normally complete the level with around 100s left on the timer, others might run out of time on their first try.
This is a tileset I worked really hard on. With this tileset, you can create "3D" looking blocks. Please give credit if you use this.
This tileset works best in a Layer 2 level with the interactive parts on layer 2 with priority off and the foreground on layer 1 with priority on. In the first screenshot and the sample level, the green parts are on Layer 1 and the yellow parts are on layer 2.
If I am missing something or have any more questions/doubts, please leave them in the comment section.
Doesn't use custom palettes; works with vanilla palettes 3, 5, 6 and 7.