When a player tryes to add a homepoint on a iceberg it gives the message "you can only use a home location on a foundation" ive tried on a foundation, roofs, normal floors etc still doesnt work. Please fix this!

have u got dynamic cupboards plugin if so its in the config - turn it off

So, this is still the case if "AllowIceberg": true ?  For me, it does not.  I realize the error is a little nebulous.  This detection is some older code but does allow you to sethome if this setting is true, ime.