Problems patching DC games

[Webhead]

Hello, i,m looking for some help/info on patching dc games.

I've patched some games using pal patcher, ppf omatic and applyppf but only had limited sucess.

Almost all of the time when using a ppf file for a particular game I always get a message that the file is the "incorrect size" do you want to continue. When you do continue the patch is normally applied.
Sometimes the patches work, sometimes they dont.

I'm having a particular problem with Streetfighter Alpha 3 where the game only works with an rf lead (scart/rgb dosent work).

I've used the rgb patch but this has no effect.
I've read in other posts that using a hex editor will solve this problem but I have no idea how to use one.

I also have a similar problem with jojo's bizare adventure but that only boots to a blank screen and will not start.

Can anyone help?