The purple/green area graphic that's overlayed on top of the electric furnace 1 graphic is misplaced - it looks like it was intended on being placed on a 2x2 furnace, instead of a 3x3 one? (Not using WaiTex)

I'm not getting that issue.

Electric furnaces actually still use the old non-HD graphics, and when checking, look as intended for me.

Can also confirm this issue. It looks like the green/purple painting is off by a few pixels. Here is a screenshot:
http://steamcommunity.com/sharedfiles/filedetails/?id=917193750

Thanks for the screenshot TehFocus - exactly how mine look too. Bob - if it helps, my possibly relevant graphics options are:
Allow Texture Compression - unchecked
UI Scale - system default (100%)
Sprite Resolution - High
Video Memory Usage - All

I'm running the game windowed, and maximized. 2560x1440 monitor.

Same here, broken as well on my end!