Forge 14.23.2.2651
IE 0.12-80

Floodlight always lights up in the back of the shown direction when placed on the wall.

Now tested, the esat wall has the problem but the west doesn't

I haven't been able to replicate this. Please upload a full modlist, try updating IE to build 81 (I doubt that will fix it, but it's good practice to use the latest version for bug reports) and test whether this happens in a test world (something like a creative superflat world).