There is a good post on this about 2 years ago. The reason for this post is to help explain so problems. In april 94 an errata was published about the unstabe nature and not beig able to set current. to solve this remove C16 and re solder the botton to R35 (ie not to R36). Also you may beed to remove C3 from the RV1 pot.
In feb95 the three(3) connections for the power transformer. the CT connection shown on the right should be on the left. the OV line will be as the schematic.
I hope this additional information help new constructors and other with problems.