While this is an absurdly old post to reply to, given that this bug is still present (and bugged the snot out of me) I felt the need to provide a fix (although I only halfway know what I'm doing).
The quick fix:
Go to your mods folder, unzip the mod, and open data.lua. Change lines 97, 113, and 137 so that scale = 2 (instead of 4). Afterwards, re-zip the folder, make sure that the name of the folder inside the .zip is correct, and you're good to go.
Explanation:
The origin of this bug is with the graphics scaling in the data.lua. In most cases, the high resolution image is just that -- higher resolution. For this reason, the scale parameter exists. In this mod, both the normal graphic and high resolution graphic are using the same graphic (as seen by lines 91, 99, 108, 117, 132, and 140 in data.lua). Despite this, the scale parameter differs between the high resolution and normal sprites, leading to this issue.
Sorry for the necro-post, but I hope this helps out. Thanks for the mod poxydoxy!