Shader doesn't work on 1.20.1 Iris

[UAPvP]

Error:
deferred.fsh: deferred.fsh: 0(667) : error C1115: unable to find compatible overloaded function "getCustomLightmap(vec3, float, vec3)"

GPU: gtx1650Ti mobile
CPU: AMD 5 3550h
Windows 11
Also I have Vivecraft(VR mod), but shader doesn't work even if I disable the mod.

[DrDesten]

This definitely looks like a me issue. Does it only happen on 1.20.1 or also on previous versions?
Also, could you provide your settings file just in case. (You can find it in the shaderpacks directory under the same name as the pack but ending in '.txt')

Unfortunately I'm pretty busy at the moment, so it might take me till next weekend to release a fix.