I found out the cause for this problem: In v3 the tp2 had the lines:
READ_2DA_ENTRY row 23 (23 + "%IK_EDWIN_KIT%") "conj"
SET_2DA_ENTRY row (22 + "%IK_EDWIN_KIT%") (23 + "%IK_EDWIN_KIT%") ~%conj%~
In v4 those lines were changed into:
READ_2DA_ENTRY row 23 (22 + "%IK_EDWIN_KIT%") "conj"
SET_2DA_ENTRY row (21 + "%IK_EDWIN_KIT%") (22 + "%IK_EDWIN_KIT%") ~%conj%~
As a result of this, in the weapprof.2da the column IK_BATTLERAGER is replaced by another column. I have changed this back to the former code and now Refinements installs fa