Vanilla Graphics Mixer is a tool to simplify the process of merging Super Mario World sprite GFX files. This allows you to use combinations of sprites that don't appear in the original game (Dry bones + Mechakoopas, for example).
Start by selecting sprites from the list on the right. Sprites that conflict with your selections
will turn grey, and the preview tooltip will show which parts of the sprite will have the wrong tiles.
If a sprite is fully incompatible then it will be disabled.
The panel on the left shows the full graphics sheet. You can change the selected palette by scrolling.
Selected sprites will appear in a list below the gfx panel. Sprites with tile conflicts will be
highlighted.
Clicking on a sprite from the list will remove it.
The random button will fill remainging space in the gfx file with randomly selected sprites. It
will only choose sprites that do not conflict with what you've already selected, and won't pick anything
from the "misc" category.
To get the graphics into your romhack, make sure to download both SP3 and SP4 gfx files and insert them
as ExGFX. If you don't know how to do that, check out the
SMWCentral FAQ.
Report it on the github please! You can also request features there (no promises).
Yes.