Yeah, me too. I managed to load the mod by changing all lines in
prototypes/entity.lua
from
filename = "base/graphics/entity/cloud/cloud-45-frames.png",
to
filename = "WipMod_HeavyTank/graphics/entities/cloud/cloud-45-frames.png",
If the mod works correctly I don't know yet, it loads, all research is there, but I haven't tested the stuff yet
And you will have to make the folder and get the cloud-45-frames.png file, either from pre 2.0 version, or use some other graphics.