Curve Widening won't work

This is just a quess, but the commas (0,25) should be decimals (0.25)
R. W. Bradshaw

I think it's ok with the commas when I look at the drawing settings and I've tried with a dot.

//Christiaan

I can easily reproduce the error if Windows regional settings use a . as decimal separator and , is used in the widening table. With , (Windows) and , (table) it does work. With , and . it does work. with . and , I get the error.

Another question:

Curve Widening won't work on a imported ALG file, If i Create Civil geometry it works fine, is the a work around for?

I don't see any reason why it doesn't work from an imported ALG. Did you import with "Create Civil Rules" checked?