I know there was already a topic about that some time ago, but I didnt read it so: I cant open 1.23 reps with WEG master.Why is that and is there any new version or ?

Well, it's W3G Master, the program is really old (2003..) and there was never newer version released, so just find another program. W3G Master doesn't work anymore and I really doubt that there will be a new version ever.