I am organizing the Imagemod, and compiling everything on my computer, so I guess I am in charge
Usually, if you have a lot of images (for a particular image pack) that you know you will be making/submitting, I will allocate a number of rows. If you only have a few, then I will renumber what you send and fit it in the gaps to keep the total file size down.
As for submitting, I prefer to have all the minis in one file (easier to copy-paste). Other than that, just make sure you have the portraits and the minis matching with the correct filenumbers (eg: comp###.bmp).
Please zip the entire package, and be sure to include a credits.txt, which I will paste into the readme along with the final image numbers that you've submitted.
Uploading to shrapnel and posting a link in this thread is OK.
If my server is Online (Current status:

), then you can also upload to
my FTP site