Hi Jeff,
sorry for the long waiting time. I'll do a quick guide for you, on how to replace any epi/prologue image.
I still have to do some testing regarding wheter it's possible to add new images, but I fear it might be a dead end.
Anyway, for now we can replace images using these programs.
Download Namerutan's ResHelper here:
https://drive.google.com/file/d/0B9qanH ... 9aeUk/view
Download freeware photoediting program Gimp (simply search for it, it's free at their website).
1) Open the ResHelper. Select File -> Open -> ResourcePack. Locate the heroes4.h4r file (or x2.h4r for the expansion ones) in your Data folder and open it.
2) Find 'Layers' -> Campaign_Splashscreens. (192x154 are the small images viewable in the editor/campaign menu - 426x340 are the large images viewable in game). (Menu screens are placed under bitmap_raw.)
3) Select the one you want to replace. Go to File -> Export (this will export just that single image - you can choose to export all if want).
4) Now open the exported image in Gimp. Press tab to open the layer window if it isn't already present. Then you should see the image presented as 'misc->Frame 001'. Mark the Frame 001. Now you simply need to paste in your desired image with the proper size proportions that match the image (192x154 pixels or 426x340 pixels. Either edit your image in Gimp or paste it from another photo editing program.
5) Once pasted, go to File -> and either overwrite or export as (original file name).ora
In my case I saved it as layers.Campaign_Splashscreens.192x154.Ambush.ora
6) Switch to the ResHelper. Go to File -> Import -> Layers. Select your file and open it. Your newly changed image should appear in the ResHelper.
7) Go to File -> Save. The ResHelper should automatically suggest to save your file as (imported file name).h4d
In my case it would be layers.Campaign_Splashscreens.192x154.Ambush.h4d. Now save it.
8) Copy/move your save h4d file to your Data folder. Now you can either view the modified image in the editor or launch the game to see the changes.
Let me know if this works out for you, or if you need further help. I hope a written guide is sufficient.
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