To hex edit with FCEUX, open the rom in the emulator and select "debug" from the top menu

Next, select "Hex Editor" from the dropdown menu

Finally, select "ROM file" from the View dropdown menu

When you find an address you want to change, you'll need to find the corresponding value next

Let's say, for example, you want to change the palette of map 1. You'll note that the range of addresses for map palettes is 0x36BE2-0x36CA1

The addresses on the left don't have the 6th's digit, however. That digit actually represents the column that you'll look for

So for 0x36BE2, that would correspond to the highlighted value below (60). From there, type in the new value you want to replace 60

For most of these, it will take some trial and error to determine which values correspond with which aspect of the game you want to change

For instance, the map palettes range from 0x36BE2-0x36CA1, but these constitute each map, as well as the various objects in each map (water, dirt, etc.)

With a tiny bit of trial and error, it should be easy to edit what you need to edit using the corresponding address ranges

You need to change both of these addressed in order for the lives to be correct

For quick reference: 19 in hex = 25 lives. 32 in hex = 50 lives, 5A = 90 lives

For '0x1842D-0x18435' -> this constitutes which map uses which palette. Change w3's value to w7 if you want to make it use w7's palette values

It's very important to note that you NEED to change this to prevent w1 and w3 from using the same palettes

Both addresses should be edited for each map in order to play the correct music