I managed to finish up the V1 image encoder in late September. Unfortunately, while it seems to decode and encode images okay, it doesn't seem to produce files useable by "scummrp", so you can't insert the images back into the game resources. (attempting to do so will give an error about an unexpected object image offset)
I have a feeling this is a shortcoming in scummrp. Unfortunately, I don't know how to resolve this issue, short of writing my own V1 resource packer, and I don't want to work on that at the moment.
Anyway, I'm posting the binaries and source of the image encoder.
The V1 image format is quite interesting, since it was developed for the Commodore 64. It's kind of a tiled format, which shares some data between backgrounds and objects. I'd like to post more details but lack motivation, however the ReadMe file should explain the ins and outs.