multi line problems

hi,

I hope someone can shed some light on this.

i have started using multi lines a lot. we do curtain walling screens so it is useful to be able to draw 50mm wide lines.

the problems is since i have started using them i am getting loads of errors and when i recover the drawing it always deletes the multi lines, especially if have infilled them with colour?

also i have been using them with a vba thing i am working on at the minute but since i have started running the vba tool the multi line style form will not open?

'sets the mlstyle to ""
ThisDrawing.SetVariable "CMLSTYLE", "STANDARD" '<--style name

i assume this is having some effect on autocad but i am not sure how to fix it? when i say it wont open what happens is it looks like autocad as doing something, or waiting on something but it just freezes then beeps if i click on it. when i give up and press escape "_mlstyle" appears in the command line. i no this means it was the last command used but i am just trying to give as much info as possible.

thanks for any help or suggestions.

Cheers,

col.