Fixed: I downloaded Satan Paint (spaint.exe) and dos4gw.exe (to run spaint.exe under DOS). I used DOSBox to run spaint.exe and I created the .pcx (blank image) that were missing in the icons.spe file (from the nums0016.pcx to the nums0045.pcx), so I created a new icons.spe file and now it works correctly .
Here is the modified icons.spe file to work: https://github.com/Xenoveritas/abuse/files/2264348/icons.zip