ladder editing issue GX Works 3 glitch?

[Crocket 3]

Hi all,

I have a program I am editing in ladder mode

It is getting quite large, nearly 30k steps now

At some point after a continuous paste (I think) the editing has become glitchy

If you try and change an item it inserts the new one and keeps the old one

It puts in horizontal and vertical lines seemingly randomly which you have to play around to delete before conversion

It is only this one program

I tried editing on 2 pc's, no different

I cant find anything in mitsubishi manual 

Has anyone else had same issue?

Thanks in advance

 

[Gambit 326]

You have created two posts delete one