The patches section on SMW Central is a section which is made for patches that modify the game in several ways, for example, modification of the status bar, or player's movements. Patches are much less limited than custom blocks or custom sprites, as patches can affect any part of the game.
The submitted patches are to follow guidelines. The most important guideline is that the patches are to be compatible with Xkas v0.06.
IPS files used to be accepted, but those are much more tedious to modify than Xkas patches. Nowadays, most of the IPS files that were originally in there have been converted to .asm (Xkas) format, but there are still some that aren't converted yet. Feel free to convert it to Xkas format.